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Fix: session lock use after free
[lttng-tools.git] / src / bin / lttng-sessiond / main.c
1 /*
2 * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
3 * Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License, version 2 only,
7 * as published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License along
15 * with this program; if not, write to the Free Software Foundation, Inc.,
16 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
17 */
18
19 #define _GNU_SOURCE
20 #include <getopt.h>
21 #include <grp.h>
22 #include <limits.h>
23 #include <pthread.h>
24 #include <semaphore.h>
25 #include <signal.h>
26 #include <stdio.h>
27 #include <stdlib.h>
28 #include <string.h>
29 #include <sys/mman.h>
30 #include <sys/mount.h>
31 #include <sys/resource.h>
32 #include <sys/socket.h>
33 #include <sys/stat.h>
34 #include <sys/types.h>
35 #include <sys/wait.h>
36 #include <urcu/futex.h>
37 #include <unistd.h>
38 #include <config.h>
39
40 #include <common/common.h>
41 #include <common/compat/poll.h>
42 #include <common/compat/socket.h>
43 #include <common/defaults.h>
44 #include <common/kernel-consumer/kernel-consumer.h>
45 #include <common/ust-consumer/ust-consumer.h>
46
47 #include "lttng-sessiond.h"
48 #include "channel.h"
49 #include "context.h"
50 #include "event.h"
51 #include "futex.h"
52 #include "kernel.h"
53 #include "modprobe.h"
54 #include "shm.h"
55 #include "ust-ctl.h"
56 #include "utils.h"
57
58 #define CONSUMERD_FILE "lttng-consumerd"
59
60 struct consumer_data {
61 enum lttng_consumer_type type;
62
63 pthread_t thread; /* Worker thread interacting with the consumer */
64 sem_t sem;
65
66 /* Mutex to control consumerd pid assignation */
67 pthread_mutex_t pid_mutex;
68 pid_t pid;
69
70 int err_sock;
71 int cmd_sock;
72
73 /* consumer error and command Unix socket path */
74 char err_unix_sock_path[PATH_MAX];
75 char cmd_unix_sock_path[PATH_MAX];
76 };
77
78 /* Const values */
79 const char default_home_dir[] = DEFAULT_HOME_DIR;
80 const char default_tracing_group[] = DEFAULT_TRACING_GROUP;
81 const char default_ust_sock_dir[] = DEFAULT_UST_SOCK_DIR;
82 const char default_global_apps_pipe[] = DEFAULT_GLOBAL_APPS_PIPE;
83
84 const char *progname;
85 const char *opt_tracing_group;
86 static int opt_sig_parent;
87 static int opt_verbose_consumer;
88 static int opt_daemon;
89 static int opt_no_kernel;
90 static int is_root; /* Set to 1 if the daemon is running as root */
91 static pid_t ppid; /* Parent PID for --sig-parent option */
92 static char *rundir;
93
94 /* Consumer daemon specific control data */
95 static struct consumer_data kconsumer_data = {
96 .type = LTTNG_CONSUMER_KERNEL,
97 .err_unix_sock_path = DEFAULT_KCONSUMERD_ERR_SOCK_PATH,
98 .cmd_unix_sock_path = DEFAULT_KCONSUMERD_CMD_SOCK_PATH,
99 .err_sock = -1,
100 .cmd_sock = -1,
101 };
102 static struct consumer_data ustconsumer64_data = {
103 .type = LTTNG_CONSUMER64_UST,
104 .err_unix_sock_path = DEFAULT_USTCONSUMERD64_ERR_SOCK_PATH,
105 .cmd_unix_sock_path = DEFAULT_USTCONSUMERD64_CMD_SOCK_PATH,
106 .err_sock = -1,
107 .cmd_sock = -1,
108 };
109 static struct consumer_data ustconsumer32_data = {
110 .type = LTTNG_CONSUMER32_UST,
111 .err_unix_sock_path = DEFAULT_USTCONSUMERD32_ERR_SOCK_PATH,
112 .cmd_unix_sock_path = DEFAULT_USTCONSUMERD32_CMD_SOCK_PATH,
113 .err_sock = -1,
114 .cmd_sock = -1,
115 };
116
117 static int dispatch_thread_exit;
118
119 /* Global application Unix socket path */
120 static char apps_unix_sock_path[PATH_MAX];
121 /* Global client Unix socket path */
122 static char client_unix_sock_path[PATH_MAX];
123 /* global wait shm path for UST */
124 static char wait_shm_path[PATH_MAX];
125
126 /* Sockets and FDs */
127 static int client_sock = -1;
128 static int apps_sock = -1;
129 static int kernel_tracer_fd = -1;
130 static int kernel_poll_pipe[2] = { -1, -1 };
131
132 /*
133 * Quit pipe for all threads. This permits a single cancellation point
134 * for all threads when receiving an event on the pipe.
135 */
136 static int thread_quit_pipe[2] = { -1, -1 };
137
138 /*
139 * This pipe is used to inform the thread managing application communication
140 * that a command is queued and ready to be processed.
141 */
142 static int apps_cmd_pipe[2] = { -1, -1 };
143
144 /* Pthread, Mutexes and Semaphores */
145 static pthread_t apps_thread;
146 static pthread_t reg_apps_thread;
147 static pthread_t client_thread;
148 static pthread_t kernel_thread;
149 static pthread_t dispatch_thread;
150
151
152 /*
153 * UST registration command queue. This queue is tied with a futex and uses a N
154 * wakers / 1 waiter implemented and detailed in futex.c/.h
155 *
156 * The thread_manage_apps and thread_dispatch_ust_registration interact with
157 * this queue and the wait/wake scheme.
158 */
159 static struct ust_cmd_queue ust_cmd_queue;
160
161 /*
162 * Pointer initialized before thread creation.
163 *
164 * This points to the tracing session list containing the session count and a
165 * mutex lock. The lock MUST be taken if you iterate over the list. The lock
166 * MUST NOT be taken if you call a public function in session.c.
167 *
168 * The lock is nested inside the structure: session_list_ptr->lock. Please use
169 * session_lock_list and session_unlock_list for lock acquisition.
170 */
171 static struct ltt_session_list *session_list_ptr;
172
173 int ust_consumerd64_fd = -1;
174 int ust_consumerd32_fd = -1;
175
176 static const char *consumerd32_bin = CONFIG_CONSUMERD32_BIN;
177 static const char *consumerd64_bin = CONFIG_CONSUMERD64_BIN;
178 static const char *consumerd32_libdir = CONFIG_CONSUMERD32_LIBDIR;
179 static const char *consumerd64_libdir = CONFIG_CONSUMERD64_LIBDIR;
180
181 static
182 void setup_consumerd_path(void)
183 {
184 const char *bin, *libdir;
185
186 /*
187 * Allow INSTALL_BIN_PATH to be used as a target path for the
188 * native architecture size consumer if CONFIG_CONSUMER*_PATH
189 * has not been defined.
190 */
191 #if (CAA_BITS_PER_LONG == 32)
192 if (!consumerd32_bin[0]) {
193 consumerd32_bin = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
194 }
195 if (!consumerd32_libdir[0]) {
196 consumerd32_libdir = INSTALL_LIB_PATH;
197 }
198 #elif (CAA_BITS_PER_LONG == 64)
199 if (!consumerd64_bin[0]) {
200 consumerd64_bin = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
201 }
202 if (!consumerd64_libdir[0]) {
203 consumerd64_libdir = INSTALL_LIB_PATH;
204 }
205 #else
206 #error "Unknown bitness"
207 #endif
208
209 /*
210 * runtime env. var. overrides the build default.
211 */
212 bin = getenv("LTTNG_CONSUMERD32_BIN");
213 if (bin) {
214 consumerd32_bin = bin;
215 }
216 bin = getenv("LTTNG_CONSUMERD64_BIN");
217 if (bin) {
218 consumerd64_bin = bin;
219 }
220 libdir = getenv("LTTNG_CONSUMERD32_LIBDIR");
221 if (libdir) {
222 consumerd32_libdir = libdir;
223 }
224 libdir = getenv("LTTNG_CONSUMERD64_LIBDIR");
225 if (libdir) {
226 consumerd64_libdir = libdir;
227 }
228 }
229
230 /*
231 * Create a poll set with O_CLOEXEC and add the thread quit pipe to the set.
232 */
233 static int create_thread_poll_set(struct lttng_poll_event *events,
234 unsigned int size)
235 {
236 int ret;
237
238 if (events == NULL || size == 0) {
239 ret = -1;
240 goto error;
241 }
242
243 ret = lttng_poll_create(events, size, LTTNG_CLOEXEC);
244 if (ret < 0) {
245 goto error;
246 }
247
248 /* Add quit pipe */
249 ret = lttng_poll_add(events, thread_quit_pipe[0], LPOLLIN);
250 if (ret < 0) {
251 goto error;
252 }
253
254 return 0;
255
256 error:
257 return ret;
258 }
259
260 /*
261 * Check if the thread quit pipe was triggered.
262 *
263 * Return 1 if it was triggered else 0;
264 */
265 static int check_thread_quit_pipe(int fd, uint32_t events)
266 {
267 if (fd == thread_quit_pipe[0] && (events & LPOLLIN)) {
268 return 1;
269 }
270
271 return 0;
272 }
273
274 /*
275 * Return group ID of the tracing group or -1 if not found.
276 */
277 static gid_t allowed_group(void)
278 {
279 struct group *grp;
280
281 if (opt_tracing_group) {
282 grp = getgrnam(opt_tracing_group);
283 } else {
284 grp = getgrnam(default_tracing_group);
285 }
286 if (!grp) {
287 return -1;
288 } else {
289 return grp->gr_gid;
290 }
291 }
292
293 /*
294 * Init thread quit pipe.
295 *
296 * Return -1 on error or 0 if all pipes are created.
297 */
298 static int init_thread_quit_pipe(void)
299 {
300 int ret, i;
301
302 ret = pipe(thread_quit_pipe);
303 if (ret < 0) {
304 PERROR("thread quit pipe");
305 goto error;
306 }
307
308 for (i = 0; i < 2; i++) {
309 ret = fcntl(thread_quit_pipe[i], F_SETFD, FD_CLOEXEC);
310 if (ret < 0) {
311 PERROR("fcntl");
312 goto error;
313 }
314 }
315
316 error:
317 return ret;
318 }
319
320 /*
321 * Complete teardown of a kernel session. This free all data structure related
322 * to a kernel session and update counter.
323 */
324 static void teardown_kernel_session(struct ltt_session *session)
325 {
326 if (!session->kernel_session) {
327 DBG3("No kernel session when tearing down session");
328 return;
329 }
330
331 DBG("Tearing down kernel session");
332
333 /*
334 * If a custom kernel consumer was registered, close the socket before
335 * tearing down the complete kernel session structure
336 */
337 if (kconsumer_data.cmd_sock >= 0 &&
338 session->kernel_session->consumer_fd != kconsumer_data.cmd_sock) {
339 lttcomm_close_unix_sock(session->kernel_session->consumer_fd);
340 }
341
342 trace_kernel_destroy_session(session->kernel_session);
343 }
344
345 /*
346 * Complete teardown of all UST sessions. This will free everything on his path
347 * and destroy the core essence of all ust sessions :)
348 */
349 static void teardown_ust_session(struct ltt_session *session)
350 {
351 int ret;
352
353 if (!session->ust_session) {
354 DBG3("No UST session when tearing down session");
355 return;
356 }
357
358 DBG("Tearing down UST session(s)");
359
360 ret = ust_app_destroy_trace_all(session->ust_session);
361 if (ret) {
362 ERR("Error in ust_app_destroy_trace_all");
363 }
364
365 trace_ust_destroy_session(session->ust_session);
366 }
367
368 /*
369 * Stop all threads by closing the thread quit pipe.
370 */
371 static void stop_threads(void)
372 {
373 int ret;
374
375 /* Stopping all threads */
376 DBG("Terminating all threads");
377 ret = notify_thread_pipe(thread_quit_pipe[1]);
378 if (ret < 0) {
379 ERR("write error on thread quit pipe");
380 }
381
382 /* Dispatch thread */
383 dispatch_thread_exit = 1;
384 futex_nto1_wake(&ust_cmd_queue.futex);
385 }
386
387 /*
388 * Cleanup the daemon
389 */
390 static void cleanup(void)
391 {
392 int ret, i;
393 char *cmd;
394 struct ltt_session *sess, *stmp;
395
396 DBG("Cleaning up");
397
398 DBG("Removing %s directory", rundir);
399 ret = asprintf(&cmd, "rm -rf %s", rundir);
400 if (ret < 0) {
401 ERR("asprintf failed. Something is really wrong!");
402 }
403
404 /* Remove lttng run directory */
405 ret = system(cmd);
406 if (ret < 0) {
407 ERR("Unable to clean %s", rundir);
408 }
409 free(cmd);
410
411 DBG("Cleaning up all sessions");
412
413 /* Destroy session list mutex */
414 if (session_list_ptr != NULL) {
415 pthread_mutex_destroy(&session_list_ptr->lock);
416
417 /* Cleanup ALL session */
418 cds_list_for_each_entry_safe(sess, stmp,
419 &session_list_ptr->head, list) {
420 teardown_kernel_session(sess);
421 teardown_ust_session(sess);
422 free(sess);
423 }
424 }
425
426 DBG("Closing all UST sockets");
427 ust_app_clean_list();
428
429 pthread_mutex_destroy(&kconsumer_data.pid_mutex);
430
431 if (is_root && !opt_no_kernel) {
432 DBG2("Closing kernel fd");
433 if (kernel_tracer_fd >= 0) {
434 ret = close(kernel_tracer_fd);
435 if (ret) {
436 PERROR("close");
437 }
438 }
439 DBG("Unloading kernel modules");
440 modprobe_remove_lttng_all();
441 }
442
443 /*
444 * Closing all pipes used for communication between threads.
445 */
446 for (i = 0; i < 2; i++) {
447 if (kernel_poll_pipe[i] >= 0) {
448 ret = close(kernel_poll_pipe[i]);
449 if (ret) {
450 PERROR("close");
451 }
452
453 }
454 }
455 for (i = 0; i < 2; i++) {
456 if (thread_quit_pipe[i] >= 0) {
457 ret = close(thread_quit_pipe[i]);
458 if (ret) {
459 PERROR("close");
460 }
461 }
462 }
463 for (i = 0; i < 2; i++) {
464 if (apps_cmd_pipe[i] >= 0) {
465 ret = close(apps_cmd_pipe[i]);
466 if (ret) {
467 PERROR("close");
468 }
469 }
470 }
471
472 /* <fun> */
473 DBG("%c[%d;%dm*** assert failed :-) *** ==> %c[%dm%c[%d;%dm"
474 "Matthew, BEET driven development works!%c[%dm",
475 27, 1, 31, 27, 0, 27, 1, 33, 27, 0);
476 /* </fun> */
477 }
478
479 /*
480 * Send data on a unix socket using the liblttsessiondcomm API.
481 *
482 * Return lttcomm error code.
483 */
484 static int send_unix_sock(int sock, void *buf, size_t len)
485 {
486 /* Check valid length */
487 if (len <= 0) {
488 return -1;
489 }
490
491 return lttcomm_send_unix_sock(sock, buf, len);
492 }
493
494 /*
495 * Free memory of a command context structure.
496 */
497 static void clean_command_ctx(struct command_ctx **cmd_ctx)
498 {
499 DBG("Clean command context structure");
500 if (*cmd_ctx) {
501 if ((*cmd_ctx)->llm) {
502 free((*cmd_ctx)->llm);
503 }
504 if ((*cmd_ctx)->lsm) {
505 free((*cmd_ctx)->lsm);
506 }
507 free(*cmd_ctx);
508 *cmd_ctx = NULL;
509 }
510 }
511
512 /*
513 * Send all stream fds of kernel channel to the consumer.
514 */
515 static int send_kconsumer_channel_streams(struct consumer_data *consumer_data,
516 int sock, struct ltt_kernel_channel *channel,
517 uid_t uid, gid_t gid)
518 {
519 int ret;
520 struct ltt_kernel_stream *stream;
521 struct lttcomm_consumer_msg lkm;
522
523 DBG("Sending streams of channel %s to kernel consumer",
524 channel->channel->name);
525
526 /* Send channel */
527 lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
528 lkm.u.channel.channel_key = channel->fd;
529 lkm.u.channel.max_sb_size = channel->channel->attr.subbuf_size;
530 lkm.u.channel.mmap_len = 0; /* for kernel */
531 DBG("Sending channel %d to consumer", lkm.u.channel.channel_key);
532 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
533 if (ret < 0) {
534 PERROR("send consumer channel");
535 goto error;
536 }
537
538 /* Send streams */
539 cds_list_for_each_entry(stream, &channel->stream_list.head, list) {
540 if (!stream->fd) {
541 continue;
542 }
543 lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
544 lkm.u.stream.channel_key = channel->fd;
545 lkm.u.stream.stream_key = stream->fd;
546 lkm.u.stream.state = stream->state;
547 lkm.u.stream.output = channel->channel->attr.output;
548 lkm.u.stream.mmap_len = 0; /* for kernel */
549 lkm.u.stream.uid = uid;
550 lkm.u.stream.gid = gid;
551 strncpy(lkm.u.stream.path_name, stream->pathname, PATH_MAX - 1);
552 lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
553 DBG("Sending stream %d to consumer", lkm.u.stream.stream_key);
554 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
555 if (ret < 0) {
556 PERROR("send consumer stream");
557 goto error;
558 }
559 ret = lttcomm_send_fds_unix_sock(sock, &stream->fd, 1);
560 if (ret < 0) {
561 PERROR("send consumer stream ancillary data");
562 goto error;
563 }
564 }
565
566 DBG("consumer channel streams sent");
567
568 return 0;
569
570 error:
571 return ret;
572 }
573
574 /*
575 * Send all stream fds of the kernel session to the consumer.
576 */
577 static int send_kconsumer_session_streams(struct consumer_data *consumer_data,
578 struct ltt_kernel_session *session)
579 {
580 int ret;
581 struct ltt_kernel_channel *chan;
582 struct lttcomm_consumer_msg lkm;
583 int sock = session->consumer_fd;
584
585 DBG("Sending metadata stream fd");
586
587 /* Extra protection. It's NOT supposed to be set to -1 at this point */
588 if (session->consumer_fd < 0) {
589 session->consumer_fd = consumer_data->cmd_sock;
590 }
591
592 if (session->metadata_stream_fd >= 0) {
593 /* Send metadata channel fd */
594 lkm.cmd_type = LTTNG_CONSUMER_ADD_CHANNEL;
595 lkm.u.channel.channel_key = session->metadata->fd;
596 lkm.u.channel.max_sb_size = session->metadata->conf->attr.subbuf_size;
597 lkm.u.channel.mmap_len = 0; /* for kernel */
598 DBG("Sending metadata channel %d to consumer", lkm.u.channel.channel_key);
599 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
600 if (ret < 0) {
601 PERROR("send consumer channel");
602 goto error;
603 }
604
605 /* Send metadata stream fd */
606 lkm.cmd_type = LTTNG_CONSUMER_ADD_STREAM;
607 lkm.u.stream.channel_key = session->metadata->fd;
608 lkm.u.stream.stream_key = session->metadata_stream_fd;
609 lkm.u.stream.state = LTTNG_CONSUMER_ACTIVE_STREAM;
610 lkm.u.stream.output = DEFAULT_KERNEL_CHANNEL_OUTPUT;
611 lkm.u.stream.mmap_len = 0; /* for kernel */
612 lkm.u.stream.uid = session->uid;
613 lkm.u.stream.gid = session->gid;
614 strncpy(lkm.u.stream.path_name, session->metadata->pathname, PATH_MAX - 1);
615 lkm.u.stream.path_name[PATH_MAX - 1] = '\0';
616 DBG("Sending metadata stream %d to consumer", lkm.u.stream.stream_key);
617 ret = lttcomm_send_unix_sock(sock, &lkm, sizeof(lkm));
618 if (ret < 0) {
619 PERROR("send consumer stream");
620 goto error;
621 }
622 ret = lttcomm_send_fds_unix_sock(sock, &session->metadata_stream_fd, 1);
623 if (ret < 0) {
624 PERROR("send consumer stream");
625 goto error;
626 }
627 }
628
629 cds_list_for_each_entry(chan, &session->channel_list.head, list) {
630 ret = send_kconsumer_channel_streams(consumer_data, sock, chan,
631 session->uid, session->gid);
632 if (ret < 0) {
633 goto error;
634 }
635 }
636
637 DBG("consumer fds (metadata and channel streams) sent");
638
639 return 0;
640
641 error:
642 return ret;
643 }
644
645 /*
646 * Notify UST applications using the shm mmap futex.
647 */
648 static int notify_ust_apps(int active)
649 {
650 char *wait_shm_mmap;
651
652 DBG("Notifying applications of session daemon state: %d", active);
653
654 /* See shm.c for this call implying mmap, shm and futex calls */
655 wait_shm_mmap = shm_ust_get_mmap(wait_shm_path, is_root);
656 if (wait_shm_mmap == NULL) {
657 goto error;
658 }
659
660 /* Wake waiting process */
661 futex_wait_update((int32_t *) wait_shm_mmap, active);
662
663 /* Apps notified successfully */
664 return 0;
665
666 error:
667 return -1;
668 }
669
670 /*
671 * Setup the outgoing data buffer for the response (llm) by allocating the
672 * right amount of memory and copying the original information from the lsm
673 * structure.
674 *
675 * Return total size of the buffer pointed by buf.
676 */
677 static int setup_lttng_msg(struct command_ctx *cmd_ctx, size_t size)
678 {
679 int ret, buf_size;
680
681 buf_size = size;
682
683 cmd_ctx->llm = zmalloc(sizeof(struct lttcomm_lttng_msg) + buf_size);
684 if (cmd_ctx->llm == NULL) {
685 PERROR("zmalloc");
686 ret = -ENOMEM;
687 goto error;
688 }
689
690 /* Copy common data */
691 cmd_ctx->llm->cmd_type = cmd_ctx->lsm->cmd_type;
692 cmd_ctx->llm->pid = cmd_ctx->lsm->domain.attr.pid;
693
694 cmd_ctx->llm->data_size = size;
695 cmd_ctx->lttng_msg_size = sizeof(struct lttcomm_lttng_msg) + buf_size;
696
697 return buf_size;
698
699 error:
700 return ret;
701 }
702
703 /*
704 * Update the kernel poll set of all channel fd available over all tracing
705 * session. Add the wakeup pipe at the end of the set.
706 */
707 static int update_kernel_poll(struct lttng_poll_event *events)
708 {
709 int ret;
710 struct ltt_session *session;
711 struct ltt_kernel_channel *channel;
712
713 DBG("Updating kernel poll set");
714
715 session_lock_list();
716 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
717 session_lock(session);
718 if (session->kernel_session == NULL) {
719 session_unlock(session);
720 continue;
721 }
722
723 cds_list_for_each_entry(channel,
724 &session->kernel_session->channel_list.head, list) {
725 /* Add channel fd to the kernel poll set */
726 ret = lttng_poll_add(events, channel->fd, LPOLLIN | LPOLLRDNORM);
727 if (ret < 0) {
728 session_unlock(session);
729 goto error;
730 }
731 DBG("Channel fd %d added to kernel set", channel->fd);
732 }
733 session_unlock(session);
734 }
735 session_unlock_list();
736
737 return 0;
738
739 error:
740 session_unlock_list();
741 return -1;
742 }
743
744 /*
745 * Find the channel fd from 'fd' over all tracing session. When found, check
746 * for new channel stream and send those stream fds to the kernel consumer.
747 *
748 * Useful for CPU hotplug feature.
749 */
750 static int update_kernel_stream(struct consumer_data *consumer_data, int fd)
751 {
752 int ret = 0;
753 struct ltt_session *session;
754 struct ltt_kernel_channel *channel;
755
756 DBG("Updating kernel streams for channel fd %d", fd);
757
758 session_lock_list();
759 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
760 session_lock(session);
761 if (session->kernel_session == NULL) {
762 session_unlock(session);
763 continue;
764 }
765
766 /* This is not suppose to be -1 but this is an extra security check */
767 if (session->kernel_session->consumer_fd < 0) {
768 session->kernel_session->consumer_fd = consumer_data->cmd_sock;
769 }
770
771 cds_list_for_each_entry(channel,
772 &session->kernel_session->channel_list.head, list) {
773 if (channel->fd == fd) {
774 DBG("Channel found, updating kernel streams");
775 ret = kernel_open_channel_stream(channel);
776 if (ret < 0) {
777 goto error;
778 }
779
780 /*
781 * Have we already sent fds to the consumer? If yes, it means
782 * that tracing is started so it is safe to send our updated
783 * stream fds.
784 */
785 if (session->kernel_session->consumer_fds_sent == 1) {
786 ret = send_kconsumer_channel_streams(consumer_data,
787 session->kernel_session->consumer_fd, channel,
788 session->uid, session->gid);
789 if (ret < 0) {
790 goto error;
791 }
792 }
793 goto error;
794 }
795 }
796 session_unlock(session);
797 }
798 session_unlock_list();
799 return ret;
800
801 error:
802 session_unlock(session);
803 session_unlock_list();
804 return ret;
805 }
806
807 /*
808 * For each tracing session, update newly registered apps.
809 */
810 static void update_ust_app(int app_sock)
811 {
812 struct ltt_session *sess, *stmp;
813
814 session_lock_list();
815
816 /* For all tracing session(s) */
817 cds_list_for_each_entry_safe(sess, stmp, &session_list_ptr->head, list) {
818 session_lock(sess);
819 if (sess->ust_session) {
820 ust_app_global_update(sess->ust_session, app_sock);
821 }
822 session_unlock(sess);
823 }
824
825 session_unlock_list();
826 }
827
828 /*
829 * This thread manage event coming from the kernel.
830 *
831 * Features supported in this thread:
832 * -) CPU Hotplug
833 */
834 static void *thread_manage_kernel(void *data)
835 {
836 int ret, i, pollfd, update_poll_flag = 1;
837 uint32_t revents, nb_fd;
838 char tmp;
839 struct lttng_poll_event events;
840
841 DBG("Thread manage kernel started");
842
843 ret = create_thread_poll_set(&events, 2);
844 if (ret < 0) {
845 goto error_poll_create;
846 }
847
848 ret = lttng_poll_add(&events, kernel_poll_pipe[0], LPOLLIN);
849 if (ret < 0) {
850 goto error;
851 }
852
853 while (1) {
854 if (update_poll_flag == 1) {
855 /*
856 * Reset number of fd in the poll set. Always 2 since there is the thread
857 * quit pipe and the kernel pipe.
858 */
859 events.nb_fd = 2;
860
861 ret = update_kernel_poll(&events);
862 if (ret < 0) {
863 goto error;
864 }
865 update_poll_flag = 0;
866 }
867
868 nb_fd = LTTNG_POLL_GETNB(&events);
869
870 DBG("Thread kernel polling on %d fds", nb_fd);
871
872 /* Zeroed the poll events */
873 lttng_poll_reset(&events);
874
875 /* Poll infinite value of time */
876 restart:
877 ret = lttng_poll_wait(&events, -1);
878 if (ret < 0) {
879 /*
880 * Restart interrupted system call.
881 */
882 if (errno == EINTR) {
883 goto restart;
884 }
885 goto error;
886 } else if (ret == 0) {
887 /* Should not happen since timeout is infinite */
888 ERR("Return value of poll is 0 with an infinite timeout.\n"
889 "This should not have happened! Continuing...");
890 continue;
891 }
892
893 for (i = 0; i < nb_fd; i++) {
894 /* Fetch once the poll data */
895 revents = LTTNG_POLL_GETEV(&events, i);
896 pollfd = LTTNG_POLL_GETFD(&events, i);
897
898 /* Thread quit pipe has been closed. Killing thread. */
899 ret = check_thread_quit_pipe(pollfd, revents);
900 if (ret) {
901 goto error;
902 }
903
904 /* Check for data on kernel pipe */
905 if (pollfd == kernel_poll_pipe[0] && (revents & LPOLLIN)) {
906 ret = read(kernel_poll_pipe[0], &tmp, 1);
907 update_poll_flag = 1;
908 continue;
909 } else {
910 /*
911 * New CPU detected by the kernel. Adding kernel stream to
912 * kernel session and updating the kernel consumer
913 */
914 if (revents & LPOLLIN) {
915 ret = update_kernel_stream(&kconsumer_data, pollfd);
916 if (ret < 0) {
917 continue;
918 }
919 break;
920 /*
921 * TODO: We might want to handle the LPOLLERR | LPOLLHUP
922 * and unregister kernel stream at this point.
923 */
924 }
925 }
926 }
927 }
928
929 error:
930 lttng_poll_clean(&events);
931 error_poll_create:
932 DBG("Kernel thread dying");
933 return NULL;
934 }
935
936 /*
937 * This thread manage the consumer error sent back to the session daemon.
938 */
939 static void *thread_manage_consumer(void *data)
940 {
941 int sock = -1, i, ret, pollfd;
942 uint32_t revents, nb_fd;
943 enum lttcomm_return_code code;
944 struct lttng_poll_event events;
945 struct consumer_data *consumer_data = data;
946
947 DBG("[thread] Manage consumer started");
948
949 ret = lttcomm_listen_unix_sock(consumer_data->err_sock);
950 if (ret < 0) {
951 goto error_listen;
952 }
953
954 /*
955 * Pass 2 as size here for the thread quit pipe and kconsumerd_err_sock.
956 * Nothing more will be added to this poll set.
957 */
958 ret = create_thread_poll_set(&events, 2);
959 if (ret < 0) {
960 goto error_poll;
961 }
962
963 ret = lttng_poll_add(&events, consumer_data->err_sock, LPOLLIN | LPOLLRDHUP);
964 if (ret < 0) {
965 goto error;
966 }
967
968 nb_fd = LTTNG_POLL_GETNB(&events);
969
970 /* Inifinite blocking call, waiting for transmission */
971 restart:
972 ret = lttng_poll_wait(&events, -1);
973 if (ret < 0) {
974 /*
975 * Restart interrupted system call.
976 */
977 if (errno == EINTR) {
978 goto restart;
979 }
980 goto error;
981 }
982
983 for (i = 0; i < nb_fd; i++) {
984 /* Fetch once the poll data */
985 revents = LTTNG_POLL_GETEV(&events, i);
986 pollfd = LTTNG_POLL_GETFD(&events, i);
987
988 /* Thread quit pipe has been closed. Killing thread. */
989 ret = check_thread_quit_pipe(pollfd, revents);
990 if (ret) {
991 goto error;
992 }
993
994 /* Event on the registration socket */
995 if (pollfd == consumer_data->err_sock) {
996 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
997 ERR("consumer err socket poll error");
998 goto error;
999 }
1000 }
1001 }
1002
1003 sock = lttcomm_accept_unix_sock(consumer_data->err_sock);
1004 if (sock < 0) {
1005 goto error;
1006 }
1007
1008 DBG2("Receiving code from consumer err_sock");
1009
1010 /* Getting status code from kconsumerd */
1011 ret = lttcomm_recv_unix_sock(sock, &code,
1012 sizeof(enum lttcomm_return_code));
1013 if (ret <= 0) {
1014 goto error;
1015 }
1016
1017 if (code == CONSUMERD_COMMAND_SOCK_READY) {
1018 consumer_data->cmd_sock =
1019 lttcomm_connect_unix_sock(consumer_data->cmd_unix_sock_path);
1020 if (consumer_data->cmd_sock < 0) {
1021 sem_post(&consumer_data->sem);
1022 PERROR("consumer connect");
1023 goto error;
1024 }
1025 /* Signal condition to tell that the kconsumerd is ready */
1026 sem_post(&consumer_data->sem);
1027 DBG("consumer command socket ready");
1028 } else {
1029 ERR("consumer error when waiting for SOCK_READY : %s",
1030 lttcomm_get_readable_code(-code));
1031 goto error;
1032 }
1033
1034 /* Remove the kconsumerd error sock since we've established a connexion */
1035 ret = lttng_poll_del(&events, consumer_data->err_sock);
1036 if (ret < 0) {
1037 goto error;
1038 }
1039
1040 ret = lttng_poll_add(&events, sock, LPOLLIN | LPOLLRDHUP);
1041 if (ret < 0) {
1042 goto error;
1043 }
1044
1045 /* Update number of fd */
1046 nb_fd = LTTNG_POLL_GETNB(&events);
1047
1048 /* Inifinite blocking call, waiting for transmission */
1049 restart_poll:
1050 ret = lttng_poll_wait(&events, -1);
1051 if (ret < 0) {
1052 /*
1053 * Restart interrupted system call.
1054 */
1055 if (errno == EINTR) {
1056 goto restart_poll;
1057 }
1058 goto error;
1059 }
1060
1061 for (i = 0; i < nb_fd; i++) {
1062 /* Fetch once the poll data */
1063 revents = LTTNG_POLL_GETEV(&events, i);
1064 pollfd = LTTNG_POLL_GETFD(&events, i);
1065
1066 /* Thread quit pipe has been closed. Killing thread. */
1067 ret = check_thread_quit_pipe(pollfd, revents);
1068 if (ret) {
1069 goto error;
1070 }
1071
1072 /* Event on the kconsumerd socket */
1073 if (pollfd == sock) {
1074 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1075 ERR("consumer err socket second poll error");
1076 goto error;
1077 }
1078 }
1079 }
1080
1081 /* Wait for any kconsumerd error */
1082 ret = lttcomm_recv_unix_sock(sock, &code,
1083 sizeof(enum lttcomm_return_code));
1084 if (ret <= 0) {
1085 ERR("consumer closed the command socket");
1086 goto error;
1087 }
1088
1089 ERR("consumer return code : %s", lttcomm_get_readable_code(-code));
1090
1091 error:
1092 if (consumer_data->err_sock >= 0) {
1093 ret = close(consumer_data->err_sock);
1094 if (ret) {
1095 PERROR("close");
1096 }
1097 }
1098 if (consumer_data->cmd_sock >= 0) {
1099 ret = close(consumer_data->cmd_sock);
1100 if (ret) {
1101 PERROR("close");
1102 }
1103 }
1104 if (sock >= 0) {
1105 ret = close(sock);
1106 if (ret) {
1107 PERROR("close");
1108 }
1109 }
1110
1111 unlink(consumer_data->err_unix_sock_path);
1112 unlink(consumer_data->cmd_unix_sock_path);
1113 consumer_data->pid = 0;
1114
1115 lttng_poll_clean(&events);
1116 error_poll:
1117 error_listen:
1118 DBG("consumer thread cleanup completed");
1119
1120 return NULL;
1121 }
1122
1123 /*
1124 * This thread manage application communication.
1125 */
1126 static void *thread_manage_apps(void *data)
1127 {
1128 int i, ret, pollfd;
1129 uint32_t revents, nb_fd;
1130 struct ust_command ust_cmd;
1131 struct lttng_poll_event events;
1132
1133 DBG("[thread] Manage application started");
1134
1135 rcu_register_thread();
1136 rcu_thread_online();
1137
1138 ret = create_thread_poll_set(&events, 2);
1139 if (ret < 0) {
1140 goto error_poll_create;
1141 }
1142
1143 ret = lttng_poll_add(&events, apps_cmd_pipe[0], LPOLLIN | LPOLLRDHUP);
1144 if (ret < 0) {
1145 goto error;
1146 }
1147
1148 while (1) {
1149 /* Zeroed the events structure */
1150 lttng_poll_reset(&events);
1151
1152 nb_fd = LTTNG_POLL_GETNB(&events);
1153
1154 DBG("Apps thread polling on %d fds", nb_fd);
1155
1156 /* Inifinite blocking call, waiting for transmission */
1157 restart:
1158 ret = lttng_poll_wait(&events, -1);
1159 if (ret < 0) {
1160 /*
1161 * Restart interrupted system call.
1162 */
1163 if (errno == EINTR) {
1164 goto restart;
1165 }
1166 goto error;
1167 }
1168
1169 for (i = 0; i < nb_fd; i++) {
1170 /* Fetch once the poll data */
1171 revents = LTTNG_POLL_GETEV(&events, i);
1172 pollfd = LTTNG_POLL_GETFD(&events, i);
1173
1174 /* Thread quit pipe has been closed. Killing thread. */
1175 ret = check_thread_quit_pipe(pollfd, revents);
1176 if (ret) {
1177 goto error;
1178 }
1179
1180 /* Inspect the apps cmd pipe */
1181 if (pollfd == apps_cmd_pipe[0]) {
1182 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1183 ERR("Apps command pipe error");
1184 goto error;
1185 } else if (revents & LPOLLIN) {
1186 /* Empty pipe */
1187 ret = read(apps_cmd_pipe[0], &ust_cmd, sizeof(ust_cmd));
1188 if (ret < 0 || ret < sizeof(ust_cmd)) {
1189 PERROR("read apps cmd pipe");
1190 goto error;
1191 }
1192
1193 /* Register applicaton to the session daemon */
1194 ret = ust_app_register(&ust_cmd.reg_msg,
1195 ust_cmd.sock);
1196 if (ret == -ENOMEM) {
1197 goto error;
1198 } else if (ret < 0) {
1199 break;
1200 }
1201
1202 /*
1203 * Validate UST version compatibility.
1204 */
1205 ret = ust_app_validate_version(ust_cmd.sock);
1206 if (ret >= 0) {
1207 /*
1208 * Add channel(s) and event(s) to newly registered apps
1209 * from lttng global UST domain.
1210 */
1211 update_ust_app(ust_cmd.sock);
1212 }
1213
1214 ret = ust_app_register_done(ust_cmd.sock);
1215 if (ret < 0) {
1216 /*
1217 * If the registration is not possible, we simply
1218 * unregister the apps and continue
1219 */
1220 ust_app_unregister(ust_cmd.sock);
1221 } else {
1222 /*
1223 * We just need here to monitor the close of the UST
1224 * socket and poll set monitor those by default.
1225 * Listen on POLLIN (even if we never expect any
1226 * data) to ensure that hangup wakes us.
1227 */
1228 ret = lttng_poll_add(&events, ust_cmd.sock, LPOLLIN);
1229 if (ret < 0) {
1230 goto error;
1231 }
1232
1233 DBG("Apps with sock %d added to poll set",
1234 ust_cmd.sock);
1235 }
1236
1237 break;
1238 }
1239 } else {
1240 /*
1241 * At this point, we know that a registered application made
1242 * the event at poll_wait.
1243 */
1244 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1245 /* Removing from the poll set */
1246 ret = lttng_poll_del(&events, pollfd);
1247 if (ret < 0) {
1248 goto error;
1249 }
1250
1251 /* Socket closed on remote end. */
1252 ust_app_unregister(pollfd);
1253 break;
1254 }
1255 }
1256 }
1257 }
1258
1259 error:
1260 lttng_poll_clean(&events);
1261 error_poll_create:
1262 DBG("Application communication apps thread cleanup complete");
1263 rcu_thread_offline();
1264 rcu_unregister_thread();
1265 return NULL;
1266 }
1267
1268 /*
1269 * Dispatch request from the registration threads to the application
1270 * communication thread.
1271 */
1272 static void *thread_dispatch_ust_registration(void *data)
1273 {
1274 int ret;
1275 struct cds_wfq_node *node;
1276 struct ust_command *ust_cmd = NULL;
1277
1278 DBG("[thread] Dispatch UST command started");
1279
1280 while (!dispatch_thread_exit) {
1281 /* Atomically prepare the queue futex */
1282 futex_nto1_prepare(&ust_cmd_queue.futex);
1283
1284 do {
1285 /* Dequeue command for registration */
1286 node = cds_wfq_dequeue_blocking(&ust_cmd_queue.queue);
1287 if (node == NULL) {
1288 DBG("Woken up but nothing in the UST command queue");
1289 /* Continue thread execution */
1290 break;
1291 }
1292
1293 ust_cmd = caa_container_of(node, struct ust_command, node);
1294
1295 DBG("Dispatching UST registration pid:%d ppid:%d uid:%d"
1296 " gid:%d sock:%d name:%s (version %d.%d)",
1297 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1298 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1299 ust_cmd->sock, ust_cmd->reg_msg.name,
1300 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1301 /*
1302 * Inform apps thread of the new application registration. This
1303 * call is blocking so we can be assured that the data will be read
1304 * at some point in time or wait to the end of the world :)
1305 */
1306 ret = write(apps_cmd_pipe[1], ust_cmd,
1307 sizeof(struct ust_command));
1308 if (ret < 0) {
1309 PERROR("write apps cmd pipe");
1310 if (errno == EBADF) {
1311 /*
1312 * We can't inform the application thread to process
1313 * registration. We will exit or else application
1314 * registration will not occur and tracing will never
1315 * start.
1316 */
1317 goto error;
1318 }
1319 }
1320 free(ust_cmd);
1321 } while (node != NULL);
1322
1323 /* Futex wait on queue. Blocking call on futex() */
1324 futex_nto1_wait(&ust_cmd_queue.futex);
1325 }
1326
1327 error:
1328 DBG("Dispatch thread dying");
1329 return NULL;
1330 }
1331
1332 /*
1333 * This thread manage application registration.
1334 */
1335 static void *thread_registration_apps(void *data)
1336 {
1337 int sock = -1, i, ret, pollfd;
1338 uint32_t revents, nb_fd;
1339 struct lttng_poll_event events;
1340 /*
1341 * Get allocated in this thread, enqueued to a global queue, dequeued and
1342 * freed in the manage apps thread.
1343 */
1344 struct ust_command *ust_cmd = NULL;
1345
1346 DBG("[thread] Manage application registration started");
1347
1348 ret = lttcomm_listen_unix_sock(apps_sock);
1349 if (ret < 0) {
1350 goto error_listen;
1351 }
1352
1353 /*
1354 * Pass 2 as size here for the thread quit pipe and apps socket. Nothing
1355 * more will be added to this poll set.
1356 */
1357 ret = create_thread_poll_set(&events, 2);
1358 if (ret < 0) {
1359 goto error_create_poll;
1360 }
1361
1362 /* Add the application registration socket */
1363 ret = lttng_poll_add(&events, apps_sock, LPOLLIN | LPOLLRDHUP);
1364 if (ret < 0) {
1365 goto error_poll_add;
1366 }
1367
1368 /* Notify all applications to register */
1369 ret = notify_ust_apps(1);
1370 if (ret < 0) {
1371 ERR("Failed to notify applications or create the wait shared memory.\n"
1372 "Execution continues but there might be problem for already\n"
1373 "running applications that wishes to register.");
1374 }
1375
1376 while (1) {
1377 DBG("Accepting application registration");
1378
1379 nb_fd = LTTNG_POLL_GETNB(&events);
1380
1381 /* Inifinite blocking call, waiting for transmission */
1382 restart:
1383 ret = lttng_poll_wait(&events, -1);
1384 if (ret < 0) {
1385 /*
1386 * Restart interrupted system call.
1387 */
1388 if (errno == EINTR) {
1389 goto restart;
1390 }
1391 goto error;
1392 }
1393
1394 for (i = 0; i < nb_fd; i++) {
1395 /* Fetch once the poll data */
1396 revents = LTTNG_POLL_GETEV(&events, i);
1397 pollfd = LTTNG_POLL_GETFD(&events, i);
1398
1399 /* Thread quit pipe has been closed. Killing thread. */
1400 ret = check_thread_quit_pipe(pollfd, revents);
1401 if (ret) {
1402 goto error;
1403 }
1404
1405 /* Event on the registration socket */
1406 if (pollfd == apps_sock) {
1407 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1408 ERR("Register apps socket poll error");
1409 goto error;
1410 } else if (revents & LPOLLIN) {
1411 sock = lttcomm_accept_unix_sock(apps_sock);
1412 if (sock < 0) {
1413 goto error;
1414 }
1415
1416 /* Create UST registration command for enqueuing */
1417 ust_cmd = zmalloc(sizeof(struct ust_command));
1418 if (ust_cmd == NULL) {
1419 PERROR("ust command zmalloc");
1420 goto error;
1421 }
1422
1423 /*
1424 * Using message-based transmissions to ensure we don't
1425 * have to deal with partially received messages.
1426 */
1427 ret = lttcomm_recv_unix_sock(sock, &ust_cmd->reg_msg,
1428 sizeof(struct ust_register_msg));
1429 if (ret < 0 || ret < sizeof(struct ust_register_msg)) {
1430 if (ret < 0) {
1431 PERROR("lttcomm_recv_unix_sock register apps");
1432 } else {
1433 ERR("Wrong size received on apps register");
1434 }
1435 free(ust_cmd);
1436 ret = close(sock);
1437 if (ret) {
1438 PERROR("close");
1439 }
1440 sock = -1;
1441 continue;
1442 }
1443
1444 ust_cmd->sock = sock;
1445 sock = -1;
1446
1447 DBG("UST registration received with pid:%d ppid:%d uid:%d"
1448 " gid:%d sock:%d name:%s (version %d.%d)",
1449 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1450 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1451 ust_cmd->sock, ust_cmd->reg_msg.name,
1452 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
1453
1454 /*
1455 * Lock free enqueue the registration request. The red pill
1456 * has been taken! This apps will be part of the *system*.
1457 */
1458 cds_wfq_enqueue(&ust_cmd_queue.queue, &ust_cmd->node);
1459
1460 /*
1461 * Wake the registration queue futex. Implicit memory
1462 * barrier with the exchange in cds_wfq_enqueue.
1463 */
1464 futex_nto1_wake(&ust_cmd_queue.futex);
1465 }
1466 }
1467 }
1468 }
1469
1470 error:
1471 /* Notify that the registration thread is gone */
1472 notify_ust_apps(0);
1473
1474 if (apps_sock >= 0) {
1475 ret = close(apps_sock);
1476 if (ret) {
1477 PERROR("close");
1478 }
1479 }
1480 if (sock >= 0) {
1481 ret = close(sock);
1482 if (ret) {
1483 PERROR("close");
1484 }
1485 }
1486 unlink(apps_unix_sock_path);
1487
1488 error_poll_add:
1489 lttng_poll_clean(&events);
1490 error_listen:
1491 error_create_poll:
1492 DBG("UST Registration thread cleanup complete");
1493
1494 return NULL;
1495 }
1496
1497 /*
1498 * Start the thread_manage_consumer. This must be done after a lttng-consumerd
1499 * exec or it will fails.
1500 */
1501 static int spawn_consumer_thread(struct consumer_data *consumer_data)
1502 {
1503 int ret;
1504 struct timespec timeout;
1505
1506 timeout.tv_sec = DEFAULT_SEM_WAIT_TIMEOUT;
1507 timeout.tv_nsec = 0;
1508
1509 /* Setup semaphore */
1510 ret = sem_init(&consumer_data->sem, 0, 0);
1511 if (ret < 0) {
1512 PERROR("sem_init consumer semaphore");
1513 goto error;
1514 }
1515
1516 ret = pthread_create(&consumer_data->thread, NULL,
1517 thread_manage_consumer, consumer_data);
1518 if (ret != 0) {
1519 PERROR("pthread_create consumer");
1520 ret = -1;
1521 goto error;
1522 }
1523
1524 /* Get time for sem_timedwait absolute timeout */
1525 ret = clock_gettime(CLOCK_REALTIME, &timeout);
1526 if (ret < 0) {
1527 PERROR("clock_gettime spawn consumer");
1528 /* Infinite wait for the kconsumerd thread to be ready */
1529 ret = sem_wait(&consumer_data->sem);
1530 } else {
1531 /* Normal timeout if the gettime was successful */
1532 timeout.tv_sec += DEFAULT_SEM_WAIT_TIMEOUT;
1533 ret = sem_timedwait(&consumer_data->sem, &timeout);
1534 }
1535
1536 if (ret < 0) {
1537 if (errno == ETIMEDOUT) {
1538 /*
1539 * Call has timed out so we kill the kconsumerd_thread and return
1540 * an error.
1541 */
1542 ERR("The consumer thread was never ready. Killing it");
1543 ret = pthread_cancel(consumer_data->thread);
1544 if (ret < 0) {
1545 PERROR("pthread_cancel consumer thread");
1546 }
1547 } else {
1548 PERROR("semaphore wait failed consumer thread");
1549 }
1550 goto error;
1551 }
1552
1553 pthread_mutex_lock(&consumer_data->pid_mutex);
1554 if (consumer_data->pid == 0) {
1555 ERR("Kconsumerd did not start");
1556 pthread_mutex_unlock(&consumer_data->pid_mutex);
1557 goto error;
1558 }
1559 pthread_mutex_unlock(&consumer_data->pid_mutex);
1560
1561 return 0;
1562
1563 error:
1564 return ret;
1565 }
1566
1567 /*
1568 * Join consumer thread
1569 */
1570 static int join_consumer_thread(struct consumer_data *consumer_data)
1571 {
1572 void *status;
1573 int ret;
1574
1575 if (consumer_data->pid != 0) {
1576 ret = kill(consumer_data->pid, SIGTERM);
1577 if (ret) {
1578 ERR("Error killing consumer daemon");
1579 return ret;
1580 }
1581 return pthread_join(consumer_data->thread, &status);
1582 } else {
1583 return 0;
1584 }
1585 }
1586
1587 /*
1588 * Fork and exec a consumer daemon (consumerd).
1589 *
1590 * Return pid if successful else -1.
1591 */
1592 static pid_t spawn_consumerd(struct consumer_data *consumer_data)
1593 {
1594 int ret;
1595 pid_t pid;
1596 const char *consumer_to_use;
1597 const char *verbosity;
1598 struct stat st;
1599
1600 DBG("Spawning consumerd");
1601
1602 pid = fork();
1603 if (pid == 0) {
1604 /*
1605 * Exec consumerd.
1606 */
1607 if (opt_verbose_consumer) {
1608 verbosity = "--verbose";
1609 } else {
1610 verbosity = "--quiet";
1611 }
1612 switch (consumer_data->type) {
1613 case LTTNG_CONSUMER_KERNEL:
1614 /*
1615 * Find out which consumerd to execute. We will first try the
1616 * 64-bit path, then the sessiond's installation directory, and
1617 * fallback on the 32-bit one,
1618 */
1619 DBG3("Looking for a kernel consumer at these locations:");
1620 DBG3(" 1) %s", consumerd64_bin);
1621 DBG3(" 2) %s/%s", INSTALL_BIN_PATH, CONSUMERD_FILE);
1622 DBG3(" 3) %s", consumerd32_bin);
1623 if (stat(consumerd64_bin, &st) == 0) {
1624 DBG3("Found location #1");
1625 consumer_to_use = consumerd64_bin;
1626 } else if (stat(INSTALL_BIN_PATH "/" CONSUMERD_FILE, &st) == 0) {
1627 DBG3("Found location #2");
1628 consumer_to_use = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
1629 } else if (stat(consumerd32_bin, &st) == 0) {
1630 DBG3("Found location #3");
1631 consumer_to_use = consumerd32_bin;
1632 } else {
1633 DBG("Could not find any valid consumerd executable");
1634 break;
1635 }
1636 DBG("Using kernel consumer at: %s", consumer_to_use);
1637 execl(consumer_to_use,
1638 "lttng-consumerd", verbosity, "-k",
1639 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1640 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1641 NULL);
1642 break;
1643 case LTTNG_CONSUMER64_UST:
1644 {
1645 char *tmpnew = NULL;
1646
1647 if (consumerd64_libdir[0] != '\0') {
1648 char *tmp;
1649 size_t tmplen;
1650
1651 tmp = getenv("LD_LIBRARY_PATH");
1652 if (!tmp) {
1653 tmp = "";
1654 }
1655 tmplen = strlen("LD_LIBRARY_PATH=")
1656 + strlen(consumerd64_libdir) + 1 /* : */ + strlen(tmp);
1657 tmpnew = zmalloc(tmplen + 1 /* \0 */);
1658 if (!tmpnew) {
1659 ret = -ENOMEM;
1660 goto error;
1661 }
1662 strcpy(tmpnew, "LD_LIBRARY_PATH=");
1663 strcat(tmpnew, consumerd64_libdir);
1664 if (tmp[0] != '\0') {
1665 strcat(tmpnew, ":");
1666 strcat(tmpnew, tmp);
1667 }
1668 ret = putenv(tmpnew);
1669 if (ret) {
1670 ret = -errno;
1671 goto error;
1672 }
1673 }
1674 DBG("Using 64-bit UST consumer at: %s", consumerd64_bin);
1675 ret = execl(consumerd64_bin, "lttng-consumerd", verbosity, "-u",
1676 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1677 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1678 NULL);
1679 if (consumerd64_libdir[0] != '\0') {
1680 free(tmpnew);
1681 }
1682 if (ret) {
1683 goto error;
1684 }
1685 break;
1686 }
1687 case LTTNG_CONSUMER32_UST:
1688 {
1689 char *tmpnew = NULL;
1690
1691 if (consumerd32_libdir[0] != '\0') {
1692 char *tmp;
1693 size_t tmplen;
1694
1695 tmp = getenv("LD_LIBRARY_PATH");
1696 if (!tmp) {
1697 tmp = "";
1698 }
1699 tmplen = strlen("LD_LIBRARY_PATH=")
1700 + strlen(consumerd32_libdir) + 1 /* : */ + strlen(tmp);
1701 tmpnew = zmalloc(tmplen + 1 /* \0 */);
1702 if (!tmpnew) {
1703 ret = -ENOMEM;
1704 goto error;
1705 }
1706 strcpy(tmpnew, "LD_LIBRARY_PATH=");
1707 strcat(tmpnew, consumerd32_libdir);
1708 if (tmp[0] != '\0') {
1709 strcat(tmpnew, ":");
1710 strcat(tmpnew, tmp);
1711 }
1712 ret = putenv(tmpnew);
1713 if (ret) {
1714 ret = -errno;
1715 goto error;
1716 }
1717 }
1718 DBG("Using 32-bit UST consumer at: %s", consumerd32_bin);
1719 ret = execl(consumerd32_bin, "lttng-consumerd", verbosity, "-u",
1720 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
1721 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
1722 NULL);
1723 if (consumerd32_libdir[0] != '\0') {
1724 free(tmpnew);
1725 }
1726 if (ret) {
1727 goto error;
1728 }
1729 break;
1730 }
1731 default:
1732 PERROR("unknown consumer type");
1733 exit(EXIT_FAILURE);
1734 }
1735 if (errno != 0) {
1736 PERROR("kernel start consumer exec");
1737 }
1738 exit(EXIT_FAILURE);
1739 } else if (pid > 0) {
1740 ret = pid;
1741 } else {
1742 PERROR("start consumer fork");
1743 ret = -errno;
1744 }
1745 error:
1746 return ret;
1747 }
1748
1749 /*
1750 * Spawn the consumerd daemon and session daemon thread.
1751 */
1752 static int start_consumerd(struct consumer_data *consumer_data)
1753 {
1754 int ret;
1755
1756 pthread_mutex_lock(&consumer_data->pid_mutex);
1757 if (consumer_data->pid != 0) {
1758 pthread_mutex_unlock(&consumer_data->pid_mutex);
1759 goto end;
1760 }
1761
1762 ret = spawn_consumerd(consumer_data);
1763 if (ret < 0) {
1764 ERR("Spawning consumerd failed");
1765 pthread_mutex_unlock(&consumer_data->pid_mutex);
1766 goto error;
1767 }
1768
1769 /* Setting up the consumer_data pid */
1770 consumer_data->pid = ret;
1771 DBG2("Consumer pid %d", consumer_data->pid);
1772 pthread_mutex_unlock(&consumer_data->pid_mutex);
1773
1774 DBG2("Spawning consumer control thread");
1775 ret = spawn_consumer_thread(consumer_data);
1776 if (ret < 0) {
1777 ERR("Fatal error spawning consumer control thread");
1778 goto error;
1779 }
1780
1781 end:
1782 return 0;
1783
1784 error:
1785 return ret;
1786 }
1787
1788 /*
1789 * Check version of the lttng-modules.
1790 */
1791 static int validate_lttng_modules_version(void)
1792 {
1793 return kernel_validate_version(kernel_tracer_fd);
1794 }
1795
1796 /*
1797 * Setup necessary data for kernel tracer action.
1798 */
1799 static int init_kernel_tracer(void)
1800 {
1801 int ret;
1802
1803 /* Modprobe lttng kernel modules */
1804 ret = modprobe_lttng_control();
1805 if (ret < 0) {
1806 goto error;
1807 }
1808
1809 /* Open debugfs lttng */
1810 kernel_tracer_fd = open(module_proc_lttng, O_RDWR);
1811 if (kernel_tracer_fd < 0) {
1812 DBG("Failed to open %s", module_proc_lttng);
1813 ret = -1;
1814 goto error_open;
1815 }
1816
1817 /* Validate kernel version */
1818 ret = validate_lttng_modules_version();
1819 if (ret < 0) {
1820 goto error_version;
1821 }
1822
1823 ret = modprobe_lttng_data();
1824 if (ret < 0) {
1825 goto error_modules;
1826 }
1827
1828 DBG("Kernel tracer fd %d", kernel_tracer_fd);
1829 return 0;
1830
1831 error_version:
1832 modprobe_remove_lttng_control();
1833 ret = close(kernel_tracer_fd);
1834 if (ret) {
1835 PERROR("close");
1836 }
1837 kernel_tracer_fd = -1;
1838 return LTTCOMM_KERN_VERSION;
1839
1840 error_modules:
1841 ret = close(kernel_tracer_fd);
1842 if (ret) {
1843 PERROR("close");
1844 }
1845
1846 error_open:
1847 modprobe_remove_lttng_control();
1848
1849 error:
1850 WARN("No kernel tracer available");
1851 kernel_tracer_fd = -1;
1852 if (!is_root) {
1853 return LTTCOMM_NEED_ROOT_SESSIOND;
1854 } else {
1855 return LTTCOMM_KERN_NA;
1856 }
1857 }
1858
1859 /*
1860 * Init tracing by creating trace directory and sending fds kernel consumer.
1861 */
1862 static int init_kernel_tracing(struct ltt_kernel_session *session)
1863 {
1864 int ret = 0;
1865
1866 if (session->consumer_fds_sent == 0) {
1867 /*
1868 * Assign default kernel consumer socket if no consumer assigned to the
1869 * kernel session. At this point, it's NOT supposed to be -1 but this is
1870 * an extra security check.
1871 */
1872 if (session->consumer_fd < 0) {
1873 session->consumer_fd = kconsumer_data.cmd_sock;
1874 }
1875
1876 ret = send_kconsumer_session_streams(&kconsumer_data, session);
1877 if (ret < 0) {
1878 ret = LTTCOMM_KERN_CONSUMER_FAIL;
1879 goto error;
1880 }
1881
1882 session->consumer_fds_sent = 1;
1883 }
1884
1885 error:
1886 return ret;
1887 }
1888
1889 /*
1890 * Create an UST session and add it to the session ust list.
1891 */
1892 static int create_ust_session(struct ltt_session *session,
1893 struct lttng_domain *domain)
1894 {
1895 struct ltt_ust_session *lus = NULL;
1896 int ret;
1897
1898 switch (domain->type) {
1899 case LTTNG_DOMAIN_UST:
1900 break;
1901 default:
1902 ret = LTTCOMM_UNKNOWN_DOMAIN;
1903 goto error;
1904 }
1905
1906 DBG("Creating UST session");
1907
1908 lus = trace_ust_create_session(session->path, session->id, domain);
1909 if (lus == NULL) {
1910 ret = LTTCOMM_UST_SESS_FAIL;
1911 goto error;
1912 }
1913
1914 ret = run_as_mkdir_recursive(lus->pathname, S_IRWXU | S_IRWXG,
1915 session->uid, session->gid);
1916 if (ret < 0) {
1917 if (ret != -EEXIST) {
1918 ERR("Trace directory creation error");
1919 ret = LTTCOMM_UST_SESS_FAIL;
1920 goto error;
1921 }
1922 }
1923
1924 /* The domain type dictate different actions on session creation */
1925 switch (domain->type) {
1926 case LTTNG_DOMAIN_UST:
1927 /* No ustctl for the global UST domain */
1928 break;
1929 default:
1930 ERR("Unknown UST domain on create session %d", domain->type);
1931 goto error;
1932 }
1933 lus->uid = session->uid;
1934 lus->gid = session->gid;
1935 session->ust_session = lus;
1936
1937 return LTTCOMM_OK;
1938
1939 error:
1940 free(lus);
1941 return ret;
1942 }
1943
1944 /*
1945 * Create a kernel tracer session then create the default channel.
1946 */
1947 static int create_kernel_session(struct ltt_session *session)
1948 {
1949 int ret;
1950
1951 DBG("Creating kernel session");
1952
1953 ret = kernel_create_session(session, kernel_tracer_fd);
1954 if (ret < 0) {
1955 ret = LTTCOMM_KERN_SESS_FAIL;
1956 goto error;
1957 }
1958
1959 /* Set kernel consumer socket fd */
1960 if (kconsumer_data.cmd_sock >= 0) {
1961 session->kernel_session->consumer_fd = kconsumer_data.cmd_sock;
1962 }
1963
1964 ret = run_as_mkdir_recursive(session->kernel_session->trace_path,
1965 S_IRWXU | S_IRWXG, session->uid, session->gid);
1966 if (ret < 0) {
1967 if (ret != -EEXIST) {
1968 ERR("Trace directory creation error");
1969 goto error;
1970 }
1971 }
1972 session->kernel_session->uid = session->uid;
1973 session->kernel_session->gid = session->gid;
1974
1975 error:
1976 return ret;
1977 }
1978
1979 /*
1980 * Check if the UID or GID match the session. Root user has access to all
1981 * sessions.
1982 */
1983 static int session_access_ok(struct ltt_session *session, uid_t uid, gid_t gid)
1984 {
1985 if (uid != session->uid && gid != session->gid && uid != 0) {
1986 return 0;
1987 } else {
1988 return 1;
1989 }
1990 }
1991
1992 static unsigned int lttng_sessions_count(uid_t uid, gid_t gid)
1993 {
1994 unsigned int i = 0;
1995 struct ltt_session *session;
1996
1997 DBG("Counting number of available session for UID %d GID %d",
1998 uid, gid);
1999 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
2000 /*
2001 * Only list the sessions the user can control.
2002 */
2003 if (!session_access_ok(session, uid, gid)) {
2004 continue;
2005 }
2006 i++;
2007 }
2008 return i;
2009 }
2010
2011 /*
2012 * Using the session list, filled a lttng_session array to send back to the
2013 * client for session listing.
2014 *
2015 * The session list lock MUST be acquired before calling this function. Use
2016 * session_lock_list() and session_unlock_list().
2017 */
2018 static void list_lttng_sessions(struct lttng_session *sessions, uid_t uid,
2019 gid_t gid)
2020 {
2021 unsigned int i = 0;
2022 struct ltt_session *session;
2023
2024 DBG("Getting all available session for UID %d GID %d",
2025 uid, gid);
2026 /*
2027 * Iterate over session list and append data after the control struct in
2028 * the buffer.
2029 */
2030 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
2031 /*
2032 * Only list the sessions the user can control.
2033 */
2034 if (!session_access_ok(session, uid, gid)) {
2035 continue;
2036 }
2037 strncpy(sessions[i].path, session->path, PATH_MAX);
2038 sessions[i].path[PATH_MAX - 1] = '\0';
2039 strncpy(sessions[i].name, session->name, NAME_MAX);
2040 sessions[i].name[NAME_MAX - 1] = '\0';
2041 sessions[i].enabled = session->enabled;
2042 i++;
2043 }
2044 }
2045
2046 /*
2047 * Fill lttng_channel array of all channels.
2048 */
2049 static void list_lttng_channels(int domain, struct ltt_session *session,
2050 struct lttng_channel *channels)
2051 {
2052 int i = 0;
2053 struct ltt_kernel_channel *kchan;
2054
2055 DBG("Listing channels for session %s", session->name);
2056
2057 switch (domain) {
2058 case LTTNG_DOMAIN_KERNEL:
2059 /* Kernel channels */
2060 if (session->kernel_session != NULL) {
2061 cds_list_for_each_entry(kchan,
2062 &session->kernel_session->channel_list.head, list) {
2063 /* Copy lttng_channel struct to array */
2064 memcpy(&channels[i], kchan->channel, sizeof(struct lttng_channel));
2065 channels[i].enabled = kchan->enabled;
2066 i++;
2067 }
2068 }
2069 break;
2070 case LTTNG_DOMAIN_UST:
2071 {
2072 struct lttng_ht_iter iter;
2073 struct ltt_ust_channel *uchan;
2074
2075 cds_lfht_for_each_entry(session->ust_session->domain_global.channels->ht,
2076 &iter.iter, uchan, node.node) {
2077 strncpy(channels[i].name, uchan->name, LTTNG_SYMBOL_NAME_LEN);
2078 channels[i].attr.overwrite = uchan->attr.overwrite;
2079 channels[i].attr.subbuf_size = uchan->attr.subbuf_size;
2080 channels[i].attr.num_subbuf = uchan->attr.num_subbuf;
2081 channels[i].attr.switch_timer_interval =
2082 uchan->attr.switch_timer_interval;
2083 channels[i].attr.read_timer_interval =
2084 uchan->attr.read_timer_interval;
2085 channels[i].enabled = uchan->enabled;
2086 switch (uchan->attr.output) {
2087 case LTTNG_UST_MMAP:
2088 default:
2089 channels[i].attr.output = LTTNG_EVENT_MMAP;
2090 break;
2091 }
2092 i++;
2093 }
2094 break;
2095 }
2096 default:
2097 break;
2098 }
2099 }
2100
2101 /*
2102 * Create a list of ust global domain events.
2103 */
2104 static int list_lttng_ust_global_events(char *channel_name,
2105 struct ltt_ust_domain_global *ust_global, struct lttng_event **events)
2106 {
2107 int i = 0, ret = 0;
2108 unsigned int nb_event = 0;
2109 struct lttng_ht_iter iter;
2110 struct lttng_ht_node_str *node;
2111 struct ltt_ust_channel *uchan;
2112 struct ltt_ust_event *uevent;
2113 struct lttng_event *tmp;
2114
2115 DBG("Listing UST global events for channel %s", channel_name);
2116
2117 rcu_read_lock();
2118
2119 lttng_ht_lookup(ust_global->channels, (void *)channel_name, &iter);
2120 node = lttng_ht_iter_get_node_str(&iter);
2121 if (node == NULL) {
2122 ret = -LTTCOMM_UST_CHAN_NOT_FOUND;
2123 goto error;
2124 }
2125
2126 uchan = caa_container_of(&node->node, struct ltt_ust_channel, node.node);
2127
2128 nb_event += lttng_ht_get_count(uchan->events);
2129
2130 if (nb_event == 0) {
2131 ret = nb_event;
2132 goto error;
2133 }
2134
2135 DBG3("Listing UST global %d events", nb_event);
2136
2137 tmp = zmalloc(nb_event * sizeof(struct lttng_event));
2138 if (tmp == NULL) {
2139 ret = -LTTCOMM_FATAL;
2140 goto error;
2141 }
2142
2143 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
2144 strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
2145 tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
2146 tmp[i].enabled = uevent->enabled;
2147 switch (uevent->attr.instrumentation) {
2148 case LTTNG_UST_TRACEPOINT:
2149 tmp[i].type = LTTNG_EVENT_TRACEPOINT;
2150 break;
2151 case LTTNG_UST_PROBE:
2152 tmp[i].type = LTTNG_EVENT_PROBE;
2153 break;
2154 case LTTNG_UST_FUNCTION:
2155 tmp[i].type = LTTNG_EVENT_FUNCTION;
2156 break;
2157 }
2158 tmp[i].loglevel = uevent->attr.loglevel;
2159 switch (uevent->attr.loglevel_type) {
2160 case LTTNG_UST_LOGLEVEL_ALL:
2161 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
2162 break;
2163 case LTTNG_UST_LOGLEVEL_RANGE:
2164 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_RANGE;
2165 break;
2166 case LTTNG_UST_LOGLEVEL_SINGLE:
2167 tmp[i].loglevel_type = LTTNG_EVENT_LOGLEVEL_SINGLE;
2168 break;
2169 }
2170 i++;
2171 }
2172
2173 ret = nb_event;
2174 *events = tmp;
2175
2176 error:
2177 rcu_read_unlock();
2178 return ret;
2179 }
2180
2181 /*
2182 * Fill lttng_event array of all kernel events in the channel.
2183 */
2184 static int list_lttng_kernel_events(char *channel_name,
2185 struct ltt_kernel_session *kernel_session, struct lttng_event **events)
2186 {
2187 int i = 0, ret;
2188 unsigned int nb_event;
2189 struct ltt_kernel_event *event;
2190 struct ltt_kernel_channel *kchan;
2191
2192 kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
2193 if (kchan == NULL) {
2194 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2195 goto error;
2196 }
2197
2198 nb_event = kchan->event_count;
2199
2200 DBG("Listing events for channel %s", kchan->channel->name);
2201
2202 if (nb_event == 0) {
2203 ret = nb_event;
2204 goto error;
2205 }
2206
2207 *events = zmalloc(nb_event * sizeof(struct lttng_event));
2208 if (*events == NULL) {
2209 ret = LTTCOMM_FATAL;
2210 goto error;
2211 }
2212
2213 /* Kernel channels */
2214 cds_list_for_each_entry(event, &kchan->events_list.head , list) {
2215 strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
2216 (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
2217 (*events)[i].enabled = event->enabled;
2218 switch (event->event->instrumentation) {
2219 case LTTNG_KERNEL_TRACEPOINT:
2220 (*events)[i].type = LTTNG_EVENT_TRACEPOINT;
2221 break;
2222 case LTTNG_KERNEL_KPROBE:
2223 case LTTNG_KERNEL_KRETPROBE:
2224 (*events)[i].type = LTTNG_EVENT_PROBE;
2225 memcpy(&(*events)[i].attr.probe, &event->event->u.kprobe,
2226 sizeof(struct lttng_kernel_kprobe));
2227 break;
2228 case LTTNG_KERNEL_FUNCTION:
2229 (*events)[i].type = LTTNG_EVENT_FUNCTION;
2230 memcpy(&((*events)[i].attr.ftrace), &event->event->u.ftrace,
2231 sizeof(struct lttng_kernel_function));
2232 break;
2233 case LTTNG_KERNEL_NOOP:
2234 (*events)[i].type = LTTNG_EVENT_NOOP;
2235 break;
2236 case LTTNG_KERNEL_SYSCALL:
2237 (*events)[i].type = LTTNG_EVENT_SYSCALL;
2238 break;
2239 case LTTNG_KERNEL_ALL:
2240 assert(0);
2241 break;
2242 }
2243 i++;
2244 }
2245
2246 return nb_event;
2247
2248 error:
2249 return ret;
2250 }
2251
2252 /*
2253 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
2254 */
2255 static int cmd_disable_channel(struct ltt_session *session,
2256 int domain, char *channel_name)
2257 {
2258 int ret;
2259 struct ltt_ust_session *usess;
2260
2261 usess = session->ust_session;
2262
2263 switch (domain) {
2264 case LTTNG_DOMAIN_KERNEL:
2265 {
2266 ret = channel_kernel_disable(session->kernel_session,
2267 channel_name);
2268 if (ret != LTTCOMM_OK) {
2269 goto error;
2270 }
2271
2272 kernel_wait_quiescent(kernel_tracer_fd);
2273 break;
2274 }
2275 case LTTNG_DOMAIN_UST:
2276 {
2277 struct ltt_ust_channel *uchan;
2278 struct lttng_ht *chan_ht;
2279
2280 chan_ht = usess->domain_global.channels;
2281
2282 uchan = trace_ust_find_channel_by_name(chan_ht, channel_name);
2283 if (uchan == NULL) {
2284 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2285 goto error;
2286 }
2287
2288 ret = channel_ust_disable(usess, domain, uchan);
2289 if (ret != LTTCOMM_OK) {
2290 goto error;
2291 }
2292 break;
2293 }
2294 #if 0
2295 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2296 case LTTNG_DOMAIN_UST_EXEC_NAME:
2297 case LTTNG_DOMAIN_UST_PID:
2298 #endif
2299 default:
2300 ret = LTTCOMM_UNKNOWN_DOMAIN;
2301 goto error;
2302 }
2303
2304 ret = LTTCOMM_OK;
2305
2306 error:
2307 return ret;
2308 }
2309
2310 /*
2311 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
2312 */
2313 static int cmd_enable_channel(struct ltt_session *session,
2314 int domain, struct lttng_channel *attr)
2315 {
2316 int ret;
2317 struct ltt_ust_session *usess = session->ust_session;
2318 struct lttng_ht *chan_ht;
2319
2320 DBG("Enabling channel %s for session %s", attr->name, session->name);
2321
2322 switch (domain) {
2323 case LTTNG_DOMAIN_KERNEL:
2324 {
2325 struct ltt_kernel_channel *kchan;
2326
2327 kchan = trace_kernel_get_channel_by_name(attr->name,
2328 session->kernel_session);
2329 if (kchan == NULL) {
2330 ret = channel_kernel_create(session->kernel_session,
2331 attr, kernel_poll_pipe[1]);
2332 } else {
2333 ret = channel_kernel_enable(session->kernel_session, kchan);
2334 }
2335
2336 if (ret != LTTCOMM_OK) {
2337 goto error;
2338 }
2339
2340 kernel_wait_quiescent(kernel_tracer_fd);
2341 break;
2342 }
2343 case LTTNG_DOMAIN_UST:
2344 {
2345 struct ltt_ust_channel *uchan;
2346
2347 chan_ht = usess->domain_global.channels;
2348
2349 uchan = trace_ust_find_channel_by_name(chan_ht, attr->name);
2350 if (uchan == NULL) {
2351 ret = channel_ust_create(usess, domain, attr);
2352 } else {
2353 ret = channel_ust_enable(usess, domain, uchan);
2354 }
2355 break;
2356 }
2357 #if 0
2358 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2359 case LTTNG_DOMAIN_UST_EXEC_NAME:
2360 case LTTNG_DOMAIN_UST_PID:
2361 #endif
2362 default:
2363 ret = LTTCOMM_UNKNOWN_DOMAIN;
2364 goto error;
2365 }
2366
2367 error:
2368 return ret;
2369 }
2370
2371 /*
2372 * Command LTTNG_DISABLE_EVENT processed by the client thread.
2373 */
2374 static int cmd_disable_event(struct ltt_session *session, int domain,
2375 char *channel_name, char *event_name)
2376 {
2377 int ret;
2378
2379 switch (domain) {
2380 case LTTNG_DOMAIN_KERNEL:
2381 {
2382 struct ltt_kernel_channel *kchan;
2383 struct ltt_kernel_session *ksess;
2384
2385 ksess = session->kernel_session;
2386
2387 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
2388 if (kchan == NULL) {
2389 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2390 goto error;
2391 }
2392
2393 ret = event_kernel_disable_tracepoint(ksess, kchan, event_name);
2394 if (ret != LTTCOMM_OK) {
2395 goto error;
2396 }
2397
2398 kernel_wait_quiescent(kernel_tracer_fd);
2399 break;
2400 }
2401 case LTTNG_DOMAIN_UST:
2402 {
2403 struct ltt_ust_channel *uchan;
2404 struct ltt_ust_session *usess;
2405
2406 usess = session->ust_session;
2407
2408 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2409 channel_name);
2410 if (uchan == NULL) {
2411 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2412 goto error;
2413 }
2414
2415 ret = event_ust_disable_tracepoint(usess, domain, uchan, event_name);
2416 if (ret != LTTCOMM_OK) {
2417 goto error;
2418 }
2419
2420 DBG3("Disable UST event %s in channel %s completed", event_name,
2421 channel_name);
2422 break;
2423 }
2424 #if 0
2425 case LTTNG_DOMAIN_UST_EXEC_NAME:
2426 case LTTNG_DOMAIN_UST_PID:
2427 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2428 #endif
2429 default:
2430 ret = LTTCOMM_UND;
2431 goto error;
2432 }
2433
2434 ret = LTTCOMM_OK;
2435
2436 error:
2437 return ret;
2438 }
2439
2440 /*
2441 * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
2442 */
2443 static int cmd_disable_event_all(struct ltt_session *session, int domain,
2444 char *channel_name)
2445 {
2446 int ret;
2447
2448 switch (domain) {
2449 case LTTNG_DOMAIN_KERNEL:
2450 {
2451 struct ltt_kernel_session *ksess;
2452 struct ltt_kernel_channel *kchan;
2453
2454 ksess = session->kernel_session;
2455
2456 kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
2457 if (kchan == NULL) {
2458 ret = LTTCOMM_KERN_CHAN_NOT_FOUND;
2459 goto error;
2460 }
2461
2462 ret = event_kernel_disable_all(ksess, kchan);
2463 if (ret != LTTCOMM_OK) {
2464 goto error;
2465 }
2466
2467 kernel_wait_quiescent(kernel_tracer_fd);
2468 break;
2469 }
2470 case LTTNG_DOMAIN_UST:
2471 {
2472 struct ltt_ust_session *usess;
2473 struct ltt_ust_channel *uchan;
2474
2475 usess = session->ust_session;
2476
2477 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2478 channel_name);
2479 if (uchan == NULL) {
2480 ret = LTTCOMM_UST_CHAN_NOT_FOUND;
2481 goto error;
2482 }
2483
2484 ret = event_ust_disable_all_tracepoints(usess, domain, uchan);
2485 if (ret != 0) {
2486 goto error;
2487 }
2488
2489 DBG3("Disable all UST events in channel %s completed", channel_name);
2490
2491 break;
2492 }
2493 #if 0
2494 case LTTNG_DOMAIN_UST_EXEC_NAME:
2495 case LTTNG_DOMAIN_UST_PID:
2496 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2497 #endif
2498 default:
2499 ret = LTTCOMM_UND;
2500 goto error;
2501 }
2502
2503 ret = LTTCOMM_OK;
2504
2505 error:
2506 return ret;
2507 }
2508
2509 /*
2510 * Command LTTNG_ADD_CONTEXT processed by the client thread.
2511 */
2512 static int cmd_add_context(struct ltt_session *session, int domain,
2513 char *channel_name, char *event_name, struct lttng_event_context *ctx)
2514 {
2515 int ret;
2516
2517 switch (domain) {
2518 case LTTNG_DOMAIN_KERNEL:
2519 /* Add kernel context to kernel tracer */
2520 ret = context_kernel_add(session->kernel_session, ctx,
2521 event_name, channel_name);
2522 if (ret != LTTCOMM_OK) {
2523 goto error;
2524 }
2525 break;
2526 case LTTNG_DOMAIN_UST:
2527 {
2528 struct ltt_ust_session *usess = session->ust_session;
2529
2530 ret = context_ust_add(usess, domain, ctx, event_name, channel_name);
2531 if (ret != LTTCOMM_OK) {
2532 goto error;
2533 }
2534 break;
2535 }
2536 #if 0
2537 case LTTNG_DOMAIN_UST_EXEC_NAME:
2538 case LTTNG_DOMAIN_UST_PID:
2539 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2540 #endif
2541 default:
2542 ret = LTTCOMM_UND;
2543 goto error;
2544 }
2545
2546 ret = LTTCOMM_OK;
2547
2548 error:
2549 return ret;
2550 }
2551
2552 /*
2553 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2554 */
2555 static int cmd_enable_event(struct ltt_session *session, int domain,
2556 char *channel_name, struct lttng_event *event)
2557 {
2558 int ret;
2559 struct lttng_channel *attr;
2560 struct ltt_ust_session *usess = session->ust_session;
2561
2562 switch (domain) {
2563 case LTTNG_DOMAIN_KERNEL:
2564 {
2565 struct ltt_kernel_channel *kchan;
2566
2567 kchan = trace_kernel_get_channel_by_name(channel_name,
2568 session->kernel_session);
2569 if (kchan == NULL) {
2570 attr = channel_new_default_attr(domain);
2571 if (attr == NULL) {
2572 ret = LTTCOMM_FATAL;
2573 goto error;
2574 }
2575 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2576
2577 /* This call will notify the kernel thread */
2578 ret = channel_kernel_create(session->kernel_session,
2579 attr, kernel_poll_pipe[1]);
2580 if (ret != LTTCOMM_OK) {
2581 free(attr);
2582 goto error;
2583 }
2584 free(attr);
2585 }
2586
2587 /* Get the newly created kernel channel pointer */
2588 kchan = trace_kernel_get_channel_by_name(channel_name,
2589 session->kernel_session);
2590 if (kchan == NULL) {
2591 /* This sould not happen... */
2592 ret = LTTCOMM_FATAL;
2593 goto error;
2594 }
2595
2596 ret = event_kernel_enable_tracepoint(session->kernel_session, kchan,
2597 event);
2598 if (ret != LTTCOMM_OK) {
2599 goto error;
2600 }
2601
2602 kernel_wait_quiescent(kernel_tracer_fd);
2603 break;
2604 }
2605 case LTTNG_DOMAIN_UST:
2606 {
2607 struct lttng_channel *attr;
2608 struct ltt_ust_channel *uchan;
2609
2610 /* Get channel from global UST domain */
2611 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2612 channel_name);
2613 if (uchan == NULL) {
2614 /* Create default channel */
2615 attr = channel_new_default_attr(domain);
2616 if (attr == NULL) {
2617 ret = LTTCOMM_FATAL;
2618 goto error;
2619 }
2620 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2621 attr->name[NAME_MAX - 1] = '\0';
2622
2623 ret = channel_ust_create(usess, domain, attr);
2624 if (ret != LTTCOMM_OK) {
2625 free(attr);
2626 goto error;
2627 }
2628 free(attr);
2629
2630 /* Get the newly created channel reference back */
2631 uchan = trace_ust_find_channel_by_name(
2632 usess->domain_global.channels, channel_name);
2633 if (uchan == NULL) {
2634 /* Something is really wrong */
2635 ret = LTTCOMM_FATAL;
2636 goto error;
2637 }
2638 }
2639
2640 /* At this point, the session and channel exist on the tracer */
2641 ret = event_ust_enable_tracepoint(usess, domain, uchan, event);
2642 if (ret != LTTCOMM_OK) {
2643 goto error;
2644 }
2645 break;
2646 }
2647 #if 0
2648 case LTTNG_DOMAIN_UST_EXEC_NAME:
2649 case LTTNG_DOMAIN_UST_PID:
2650 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2651 #endif
2652 default:
2653 ret = LTTCOMM_UND;
2654 goto error;
2655 }
2656
2657 ret = LTTCOMM_OK;
2658
2659 error:
2660 return ret;
2661 }
2662
2663 /*
2664 * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
2665 */
2666 static int cmd_enable_event_all(struct ltt_session *session, int domain,
2667 char *channel_name, int event_type)
2668 {
2669 int ret;
2670 struct ltt_kernel_channel *kchan;
2671
2672 switch (domain) {
2673 case LTTNG_DOMAIN_KERNEL:
2674 kchan = trace_kernel_get_channel_by_name(channel_name,
2675 session->kernel_session);
2676 if (kchan == NULL) {
2677 /* This call will notify the kernel thread */
2678 ret = channel_kernel_create(session->kernel_session, NULL,
2679 kernel_poll_pipe[1]);
2680 if (ret != LTTCOMM_OK) {
2681 goto error;
2682 }
2683
2684 /* Get the newly created kernel channel pointer */
2685 kchan = trace_kernel_get_channel_by_name(channel_name,
2686 session->kernel_session);
2687 if (kchan == NULL) {
2688 /* This sould not happen... */
2689 ret = LTTCOMM_FATAL;
2690 goto error;
2691 }
2692
2693 }
2694
2695 switch (event_type) {
2696 case LTTNG_EVENT_SYSCALL:
2697 ret = event_kernel_enable_all_syscalls(session->kernel_session,
2698 kchan, kernel_tracer_fd);
2699 break;
2700 case LTTNG_EVENT_TRACEPOINT:
2701 /*
2702 * This call enables all LTTNG_KERNEL_TRACEPOINTS and
2703 * events already registered to the channel.
2704 */
2705 ret = event_kernel_enable_all_tracepoints(session->kernel_session,
2706 kchan, kernel_tracer_fd);
2707 break;
2708 case LTTNG_EVENT_ALL:
2709 /* Enable syscalls and tracepoints */
2710 ret = event_kernel_enable_all(session->kernel_session,
2711 kchan, kernel_tracer_fd);
2712 break;
2713 default:
2714 ret = LTTCOMM_KERN_ENABLE_FAIL;
2715 goto error;
2716 }
2717
2718 /* Manage return value */
2719 if (ret != LTTCOMM_OK) {
2720 goto error;
2721 }
2722
2723 kernel_wait_quiescent(kernel_tracer_fd);
2724 break;
2725 case LTTNG_DOMAIN_UST:
2726 {
2727 struct lttng_channel *attr;
2728 struct ltt_ust_channel *uchan;
2729 struct ltt_ust_session *usess = session->ust_session;
2730
2731 /* Get channel from global UST domain */
2732 uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
2733 channel_name);
2734 if (uchan == NULL) {
2735 /* Create default channel */
2736 attr = channel_new_default_attr(domain);
2737 if (attr == NULL) {
2738 ret = LTTCOMM_FATAL;
2739 goto error;
2740 }
2741 snprintf(attr->name, NAME_MAX, "%s", channel_name);
2742 attr->name[NAME_MAX - 1] = '\0';
2743
2744 /* Use the internal command enable channel */
2745 ret = channel_ust_create(usess, domain, attr);
2746 if (ret != LTTCOMM_OK) {
2747 free(attr);
2748 goto error;
2749 }
2750 free(attr);
2751
2752 /* Get the newly created channel reference back */
2753 uchan = trace_ust_find_channel_by_name(
2754 usess->domain_global.channels, channel_name);
2755 if (uchan == NULL) {
2756 /* Something is really wrong */
2757 ret = LTTCOMM_FATAL;
2758 goto error;
2759 }
2760 }
2761
2762 /* At this point, the session and channel exist on the tracer */
2763
2764 switch (event_type) {
2765 case LTTNG_EVENT_ALL:
2766 case LTTNG_EVENT_TRACEPOINT:
2767 ret = event_ust_enable_all_tracepoints(usess, domain, uchan);
2768 if (ret != LTTCOMM_OK) {
2769 goto error;
2770 }
2771 break;
2772 default:
2773 ret = LTTCOMM_UST_ENABLE_FAIL;
2774 goto error;
2775 }
2776
2777 /* Manage return value */
2778 if (ret != LTTCOMM_OK) {
2779 goto error;
2780 }
2781
2782 break;
2783 }
2784 #if 0
2785 case LTTNG_DOMAIN_UST_EXEC_NAME:
2786 case LTTNG_DOMAIN_UST_PID:
2787 case LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN:
2788 #endif
2789 default:
2790 ret = LTTCOMM_UND;
2791 goto error;
2792 }
2793
2794 ret = LTTCOMM_OK;
2795
2796 error:
2797 return ret;
2798 }
2799
2800 /*
2801 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2802 */
2803 static ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
2804 {
2805 int ret;
2806 ssize_t nb_events = 0;
2807
2808 switch (domain) {
2809 case LTTNG_DOMAIN_KERNEL:
2810 nb_events = kernel_list_events(kernel_tracer_fd, events);
2811 if (nb_events < 0) {
2812 ret = LTTCOMM_KERN_LIST_FAIL;
2813 goto error;
2814 }
2815 break;
2816 case LTTNG_DOMAIN_UST:
2817 nb_events = ust_app_list_events(events);
2818 if (nb_events < 0) {
2819 ret = LTTCOMM_UST_LIST_FAIL;
2820 goto error;
2821 }
2822 break;
2823 default:
2824 ret = LTTCOMM_UND;
2825 goto error;
2826 }
2827
2828 return nb_events;
2829
2830 error:
2831 /* Return negative value to differentiate return code */
2832 return -ret;
2833 }
2834
2835 /*
2836 * Command LTTNG_START_TRACE processed by the client thread.
2837 */
2838 static int cmd_start_trace(struct ltt_session *session)
2839 {
2840 int ret;
2841 struct ltt_kernel_session *ksession;
2842 struct ltt_ust_session *usess;
2843
2844 /* Short cut */
2845 ksession = session->kernel_session;
2846 usess = session->ust_session;
2847
2848 if (session->enabled) {
2849 /* Already started. */
2850 ret = LTTCOMM_TRACE_ALREADY_STARTED;
2851 goto error;
2852 }
2853
2854 session->enabled = 1;
2855
2856 /* Kernel tracing */
2857 if (ksession != NULL) {
2858 struct ltt_kernel_channel *kchan;
2859
2860 /* Open kernel metadata */
2861 if (ksession->metadata == NULL) {
2862 ret = kernel_open_metadata(ksession, ksession->trace_path);
2863 if (ret < 0) {
2864 ret = LTTCOMM_KERN_META_FAIL;
2865 goto error;
2866 }
2867 }
2868
2869 /* Open kernel metadata stream */
2870 if (ksession->metadata_stream_fd < 0) {
2871 ret = kernel_open_metadata_stream(ksession);
2872 if (ret < 0) {
2873 ERR("Kernel create metadata stream failed");
2874 ret = LTTCOMM_KERN_STREAM_FAIL;
2875 goto error;
2876 }
2877 }
2878
2879 /* For each channel */
2880 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2881 if (kchan->stream_count == 0) {
2882 ret = kernel_open_channel_stream(kchan);
2883 if (ret < 0) {
2884 ret = LTTCOMM_KERN_STREAM_FAIL;
2885 goto error;
2886 }
2887 /* Update the stream global counter */
2888 ksession->stream_count_global += ret;
2889 }
2890 }
2891
2892 /* Setup kernel consumer socket and send fds to it */
2893 ret = init_kernel_tracing(ksession);
2894 if (ret < 0) {
2895 ret = LTTCOMM_KERN_START_FAIL;
2896 goto error;
2897 }
2898
2899 /* This start the kernel tracing */
2900 ret = kernel_start_session(ksession);
2901 if (ret < 0) {
2902 ret = LTTCOMM_KERN_START_FAIL;
2903 goto error;
2904 }
2905
2906 /* Quiescent wait after starting trace */
2907 kernel_wait_quiescent(kernel_tracer_fd);
2908 }
2909
2910 /* Flag session that trace should start automatically */
2911 if (usess) {
2912 usess->start_trace = 1;
2913
2914 ret = ust_app_start_trace_all(usess);
2915 if (ret < 0) {
2916 ret = LTTCOMM_UST_START_FAIL;
2917 goto error;
2918 }
2919 }
2920
2921 ret = LTTCOMM_OK;
2922
2923 error:
2924 return ret;
2925 }
2926
2927 /*
2928 * Command LTTNG_STOP_TRACE processed by the client thread.
2929 */
2930 static int cmd_stop_trace(struct ltt_session *session)
2931 {
2932 int ret;
2933 struct ltt_kernel_channel *kchan;
2934 struct ltt_kernel_session *ksession;
2935 struct ltt_ust_session *usess;
2936
2937 /* Short cut */
2938 ksession = session->kernel_session;
2939 usess = session->ust_session;
2940
2941 if (!session->enabled) {
2942 ret = LTTCOMM_TRACE_ALREADY_STOPPED;
2943 goto error;
2944 }
2945
2946 session->enabled = 0;
2947
2948 /* Kernel tracer */
2949 if (ksession != NULL) {
2950 DBG("Stop kernel tracing");
2951
2952 /* Flush all buffers before stopping */
2953 ret = kernel_metadata_flush_buffer(ksession->metadata_stream_fd);
2954 if (ret < 0) {
2955 ERR("Kernel metadata flush failed");
2956 }
2957
2958 cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
2959 ret = kernel_flush_buffer(kchan);
2960 if (ret < 0) {
2961 ERR("Kernel flush buffer error");
2962 }
2963 }
2964
2965 ret = kernel_stop_session(ksession);
2966 if (ret < 0) {
2967 ret = LTTCOMM_KERN_STOP_FAIL;
2968 goto error;
2969 }
2970
2971 kernel_wait_quiescent(kernel_tracer_fd);
2972 }
2973
2974 if (usess) {
2975 usess->start_trace = 0;
2976
2977 ret = ust_app_stop_trace_all(usess);
2978 if (ret < 0) {
2979 ret = LTTCOMM_UST_STOP_FAIL;
2980 goto error;
2981 }
2982 }
2983
2984 ret = LTTCOMM_OK;
2985
2986 error:
2987 return ret;
2988 }
2989
2990 /*
2991 * Command LTTNG_CREATE_SESSION processed by the client thread.
2992 */
2993 static int cmd_create_session(char *name, char *path, lttng_sock_cred *creds)
2994 {
2995 int ret;
2996
2997 ret = session_create(name, path, LTTNG_SOCK_GET_UID_CRED(creds),
2998 LTTNG_SOCK_GET_GID_CRED(creds));
2999 if (ret != LTTCOMM_OK) {
3000 goto error;
3001 }
3002
3003 ret = LTTCOMM_OK;
3004
3005 error:
3006 return ret;
3007 }
3008
3009 /*
3010 * Command LTTNG_DESTROY_SESSION processed by the client thread.
3011 */
3012 static int cmd_destroy_session(struct ltt_session *session, char *name)
3013 {
3014 int ret;
3015
3016 /* Clean kernel session teardown */
3017 teardown_kernel_session(session);
3018 /* UST session teardown */
3019 teardown_ust_session(session);
3020
3021 /*
3022 * Must notify the kernel thread here to update it's poll setin order
3023 * to remove the channel(s)' fd just destroyed.
3024 */
3025 ret = notify_thread_pipe(kernel_poll_pipe[1]);
3026 if (ret < 0) {
3027 PERROR("write kernel poll pipe");
3028 }
3029
3030 ret = session_destroy(session);
3031
3032 return ret;
3033 }
3034
3035 /*
3036 * Command LTTNG_CALIBRATE processed by the client thread.
3037 */
3038 static int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
3039 {
3040 int ret;
3041
3042 switch (domain) {
3043 case LTTNG_DOMAIN_KERNEL:
3044 {
3045 struct lttng_kernel_calibrate kcalibrate;
3046
3047 kcalibrate.type = calibrate->type;
3048 ret = kernel_calibrate(kernel_tracer_fd, &kcalibrate);
3049 if (ret < 0) {
3050 ret = LTTCOMM_KERN_ENABLE_FAIL;
3051 goto error;
3052 }
3053 break;
3054 }
3055 case LTTNG_DOMAIN_UST:
3056 {
3057 struct lttng_ust_calibrate ucalibrate;
3058
3059 ucalibrate.type = calibrate->type;
3060 ret = ust_app_calibrate_glb(&ucalibrate);
3061 if (ret < 0) {
3062 ret = LTTCOMM_UST_CALIBRATE_FAIL;
3063 goto error;
3064 }
3065 break;
3066 }
3067 default:
3068 ret = LTTCOMM_UND;
3069 goto error;
3070 }
3071
3072 ret = LTTCOMM_OK;
3073
3074 error:
3075 return ret;
3076 }
3077
3078 /*
3079 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
3080 */
3081 static int cmd_register_consumer(struct ltt_session *session, int domain,
3082 char *sock_path)
3083 {
3084 int ret, sock;
3085
3086 switch (domain) {
3087 case LTTNG_DOMAIN_KERNEL:
3088 /* Can't register a consumer if there is already one */
3089 if (session->kernel_session->consumer_fds_sent != 0) {
3090 ret = LTTCOMM_KERN_CONSUMER_FAIL;
3091 goto error;
3092 }
3093
3094 sock = lttcomm_connect_unix_sock(sock_path);
3095 if (sock < 0) {
3096 ret = LTTCOMM_CONNECT_FAIL;
3097 goto error;
3098 }
3099
3100 session->kernel_session->consumer_fd = sock;
3101 break;
3102 default:
3103 /* TODO: Userspace tracing */
3104 ret = LTTCOMM_UND;
3105 goto error;
3106 }
3107
3108 ret = LTTCOMM_OK;
3109
3110 error:
3111 return ret;
3112 }
3113
3114 /*
3115 * Command LTTNG_LIST_DOMAINS processed by the client thread.
3116 */
3117 static ssize_t cmd_list_domains(struct ltt_session *session,
3118 struct lttng_domain **domains)
3119 {
3120 int ret, index = 0;
3121 ssize_t nb_dom = 0;
3122
3123 if (session->kernel_session != NULL) {
3124 DBG3("Listing domains found kernel domain");
3125 nb_dom++;
3126 }
3127
3128 if (session->ust_session != NULL) {
3129 DBG3("Listing domains found UST global domain");
3130 nb_dom++;
3131 }
3132
3133 *domains = zmalloc(nb_dom * sizeof(struct lttng_domain));
3134 if (*domains == NULL) {
3135 ret = -LTTCOMM_FATAL;
3136 goto error;
3137 }
3138
3139 if (session->kernel_session != NULL) {
3140 (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
3141 index++;
3142 }
3143
3144 if (session->ust_session != NULL) {
3145 (*domains)[index].type = LTTNG_DOMAIN_UST;
3146 index++;
3147 }
3148
3149 return nb_dom;
3150
3151 error:
3152 return ret;
3153 }
3154
3155 /*
3156 * Command LTTNG_LIST_CHANNELS processed by the client thread.
3157 */
3158 static ssize_t cmd_list_channels(int domain, struct ltt_session *session,
3159 struct lttng_channel **channels)
3160 {
3161 int ret;
3162 ssize_t nb_chan = 0;
3163
3164 switch (domain) {
3165 case LTTNG_DOMAIN_KERNEL:
3166 if (session->kernel_session != NULL) {
3167 nb_chan = session->kernel_session->channel_count;
3168 }
3169 DBG3("Number of kernel channels %zd", nb_chan);
3170 break;
3171 case LTTNG_DOMAIN_UST:
3172 if (session->ust_session != NULL) {
3173 nb_chan = lttng_ht_get_count(
3174 session->ust_session->domain_global.channels);
3175 }
3176 DBG3("Number of UST global channels %zd", nb_chan);
3177 break;
3178 default:
3179 *channels = NULL;
3180 ret = -LTTCOMM_UND;
3181 goto error;
3182 }
3183
3184 if (nb_chan > 0) {
3185 *channels = zmalloc(nb_chan * sizeof(struct lttng_channel));
3186 if (*channels == NULL) {
3187 ret = -LTTCOMM_FATAL;
3188 goto error;
3189 }
3190
3191 list_lttng_channels(domain, session, *channels);
3192 } else {
3193 *channels = NULL;
3194 }
3195
3196 return nb_chan;
3197
3198 error:
3199 return ret;
3200 }
3201
3202 /*
3203 * Command LTTNG_LIST_EVENTS processed by the client thread.
3204 */
3205 static ssize_t cmd_list_events(int domain, struct ltt_session *session,
3206 char *channel_name, struct lttng_event **events)
3207 {
3208 int ret = 0;
3209 ssize_t nb_event = 0;
3210
3211 switch (domain) {
3212 case LTTNG_DOMAIN_KERNEL:
3213 if (session->kernel_session != NULL) {
3214 nb_event = list_lttng_kernel_events(channel_name,
3215 session->kernel_session, events);
3216 }
3217 break;
3218 case LTTNG_DOMAIN_UST:
3219 {
3220 if (session->ust_session != NULL) {
3221 nb_event = list_lttng_ust_global_events(channel_name,
3222 &session->ust_session->domain_global, events);
3223 }
3224 break;
3225 }
3226 default:
3227 ret = -LTTCOMM_UND;
3228 goto error;
3229 }
3230
3231 ret = nb_event;
3232
3233 error:
3234 return ret;
3235 }
3236
3237 /*
3238 * Process the command requested by the lttng client within the command
3239 * context structure. This function make sure that the return structure (llm)
3240 * is set and ready for transmission before returning.
3241 *
3242 * Return any error encountered or 0 for success.
3243 */
3244 static int process_client_msg(struct command_ctx *cmd_ctx)
3245 {
3246 int ret = LTTCOMM_OK;
3247 int need_tracing_session = 1;
3248 int need_domain;
3249
3250 DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
3251
3252 switch (cmd_ctx->lsm->cmd_type) {
3253 case LTTNG_CREATE_SESSION:
3254 case LTTNG_DESTROY_SESSION:
3255 case LTTNG_LIST_SESSIONS:
3256 case LTTNG_LIST_DOMAINS:
3257 case LTTNG_START_TRACE:
3258 case LTTNG_STOP_TRACE:
3259 need_domain = 0;
3260 break;
3261 default:
3262 need_domain = 1;
3263 }
3264
3265 if (opt_no_kernel && need_domain
3266 && cmd_ctx->lsm->domain.type == LTTNG_DOMAIN_KERNEL) {
3267 if (!is_root) {
3268 ret = LTTCOMM_NEED_ROOT_SESSIOND;
3269 } else {
3270 ret = LTTCOMM_KERN_NA;
3271 }
3272 goto error;
3273 }
3274
3275 /*
3276 * Check for command that don't needs to allocate a returned payload. We do
3277 * this here so we don't have to make the call for no payload at each
3278 * command.
3279 */
3280 switch(cmd_ctx->lsm->cmd_type) {
3281 case LTTNG_LIST_SESSIONS:
3282 case LTTNG_LIST_TRACEPOINTS:
3283 case LTTNG_LIST_DOMAINS:
3284 case LTTNG_LIST_CHANNELS:
3285 case LTTNG_LIST_EVENTS:
3286 break;
3287 default:
3288 /* Setup lttng message with no payload */
3289 ret = setup_lttng_msg(cmd_ctx, 0);
3290 if (ret < 0) {
3291 /* This label does not try to unlock the session */
3292 goto init_setup_error;
3293 }
3294 }
3295
3296 /* Commands that DO NOT need a session. */
3297 switch (cmd_ctx->lsm->cmd_type) {
3298 case LTTNG_CREATE_SESSION:
3299 case LTTNG_CALIBRATE:
3300 case LTTNG_LIST_SESSIONS:
3301 case LTTNG_LIST_TRACEPOINTS:
3302 need_tracing_session = 0;
3303 break;
3304 default:
3305 DBG("Getting session %s by name", cmd_ctx->lsm->session.name);
3306 /*
3307 * We keep the session list lock across _all_ commands
3308 * for now, because the per-session lock does not
3309 * handle teardown properly.
3310 */
3311 session_lock_list();
3312 cmd_ctx->session = session_find_by_name(cmd_ctx->lsm->session.name);
3313 if (cmd_ctx->session == NULL) {
3314 if (cmd_ctx->lsm->session.name != NULL) {
3315 ret = LTTCOMM_SESS_NOT_FOUND;
3316 } else {
3317 /* If no session name specified */
3318 ret = LTTCOMM_SELECT_SESS;
3319 }
3320 goto error;
3321 } else {
3322 /* Acquire lock for the session */
3323 session_lock(cmd_ctx->session);
3324 }
3325 break;
3326 }
3327
3328 if (!need_domain) {
3329 goto skip_domain;
3330 }
3331 /*
3332 * Check domain type for specific "pre-action".
3333 */
3334 switch (cmd_ctx->lsm->domain.type) {
3335 case LTTNG_DOMAIN_KERNEL:
3336 if (!is_root) {
3337 ret = LTTCOMM_NEED_ROOT_SESSIOND;
3338 goto error;
3339 }
3340
3341 /* Kernel tracer check */
3342 if (kernel_tracer_fd == -1) {
3343 /* Basically, load kernel tracer modules */
3344 ret = init_kernel_tracer();
3345 if (ret != 0) {
3346 goto error;
3347 }
3348 }
3349
3350 /* Need a session for kernel command */
3351 if (need_tracing_session) {
3352 if (cmd_ctx->session->kernel_session == NULL) {
3353 ret = create_kernel_session(cmd_ctx->session);
3354 if (ret < 0) {
3355 ret = LTTCOMM_KERN_SESS_FAIL;
3356 goto error;
3357 }
3358 }
3359
3360 /* Start the kernel consumer daemon */
3361 pthread_mutex_lock(&kconsumer_data.pid_mutex);
3362 if (kconsumer_data.pid == 0 &&
3363 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3364 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3365 ret = start_consumerd(&kconsumer_data);
3366 if (ret < 0) {
3367 ret = LTTCOMM_KERN_CONSUMER_FAIL;
3368 goto error;
3369 }
3370 } else {
3371 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3372 }
3373 }
3374 break;
3375 case LTTNG_DOMAIN_UST:
3376 {
3377 if (need_tracing_session) {
3378 if (cmd_ctx->session->ust_session == NULL) {
3379 ret = create_ust_session(cmd_ctx->session,
3380 &cmd_ctx->lsm->domain);
3381 if (ret != LTTCOMM_OK) {
3382 goto error;
3383 }
3384 }
3385 /* Start the UST consumer daemons */
3386 /* 64-bit */
3387 pthread_mutex_lock(&ustconsumer64_data.pid_mutex);
3388 if (consumerd64_bin[0] != '\0' &&
3389 ustconsumer64_data.pid == 0 &&
3390 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3391 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
3392 ret = start_consumerd(&ustconsumer64_data);
3393 if (ret < 0) {
3394 ret = LTTCOMM_UST_CONSUMER64_FAIL;
3395 ust_consumerd64_fd = -EINVAL;
3396 goto error;
3397 }
3398
3399 ust_consumerd64_fd = ustconsumer64_data.cmd_sock;
3400 } else {
3401 pthread_mutex_unlock(&ustconsumer64_data.pid_mutex);
3402 }
3403 /* 32-bit */
3404 if (consumerd32_bin[0] != '\0' &&
3405 ustconsumer32_data.pid == 0 &&
3406 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3407 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
3408 ret = start_consumerd(&ustconsumer32_data);
3409 if (ret < 0) {
3410 ret = LTTCOMM_UST_CONSUMER32_FAIL;
3411 ust_consumerd32_fd = -EINVAL;
3412 goto error;
3413 }
3414 ust_consumerd32_fd = ustconsumer32_data.cmd_sock;
3415 } else {
3416 pthread_mutex_unlock(&ustconsumer32_data.pid_mutex);
3417 }
3418 }
3419 break;
3420 }
3421 default:
3422 break;
3423 }
3424 skip_domain:
3425
3426 /*
3427 * Check that the UID or GID match that of the tracing session.
3428 * The root user can interact with all sessions.
3429 */
3430 if (need_tracing_session) {
3431 if (!session_access_ok(cmd_ctx->session,
3432 LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds),
3433 LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds))) {
3434 ret = LTTCOMM_EPERM;
3435 goto error;
3436 }
3437 }
3438
3439 /* Process by command type */
3440 switch (cmd_ctx->lsm->cmd_type) {
3441 case LTTNG_ADD_CONTEXT:
3442 {
3443 ret = cmd_add_context(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3444 cmd_ctx->lsm->u.context.channel_name,
3445 cmd_ctx->lsm->u.context.event_name,
3446 &cmd_ctx->lsm->u.context.ctx);
3447 break;
3448 }
3449 case LTTNG_DISABLE_CHANNEL:
3450 {
3451 ret = cmd_disable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3452 cmd_ctx->lsm->u.disable.channel_name);
3453 break;
3454 }
3455 case LTTNG_DISABLE_EVENT:
3456 {
3457 ret = cmd_disable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3458 cmd_ctx->lsm->u.disable.channel_name,
3459 cmd_ctx->lsm->u.disable.name);
3460 break;
3461 }
3462 case LTTNG_DISABLE_ALL_EVENT:
3463 {
3464 DBG("Disabling all events");
3465
3466 ret = cmd_disable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3467 cmd_ctx->lsm->u.disable.channel_name);
3468 break;
3469 }
3470 case LTTNG_ENABLE_CHANNEL:
3471 {
3472 ret = cmd_enable_channel(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3473 &cmd_ctx->lsm->u.channel.chan);
3474 break;
3475 }
3476 case LTTNG_ENABLE_EVENT:
3477 {
3478 ret = cmd_enable_event(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3479 cmd_ctx->lsm->u.enable.channel_name,
3480 &cmd_ctx->lsm->u.enable.event);
3481 break;
3482 }
3483 case LTTNG_ENABLE_ALL_EVENT:
3484 {
3485 DBG("Enabling all events");
3486
3487 ret = cmd_enable_event_all(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3488 cmd_ctx->lsm->u.enable.channel_name,
3489 cmd_ctx->lsm->u.enable.event.type);
3490 break;
3491 }
3492 case LTTNG_LIST_TRACEPOINTS:
3493 {
3494 struct lttng_event *events;
3495 ssize_t nb_events;
3496
3497 nb_events = cmd_list_tracepoints(cmd_ctx->lsm->domain.type, &events);
3498 if (nb_events < 0) {
3499 ret = -nb_events;
3500 goto error;
3501 }
3502
3503 /*
3504 * Setup lttng message with payload size set to the event list size in
3505 * bytes and then copy list into the llm payload.
3506 */
3507 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_event) * nb_events);
3508 if (ret < 0) {
3509 free(events);
3510 goto setup_error;
3511 }
3512
3513 /* Copy event list into message payload */
3514 memcpy(cmd_ctx->llm->payload, events,
3515 sizeof(struct lttng_event) * nb_events);
3516
3517 free(events);
3518
3519 ret = LTTCOMM_OK;
3520 break;
3521 }
3522 case LTTNG_START_TRACE:
3523 {
3524 ret = cmd_start_trace(cmd_ctx->session);
3525 break;
3526 }
3527 case LTTNG_STOP_TRACE:
3528 {
3529 ret = cmd_stop_trace(cmd_ctx->session);
3530 break;
3531 }
3532 case LTTNG_CREATE_SESSION:
3533 {
3534 ret = cmd_create_session(cmd_ctx->lsm->session.name,
3535 cmd_ctx->lsm->session.path, &cmd_ctx->creds);
3536 break;
3537 }
3538 case LTTNG_DESTROY_SESSION:
3539 {
3540 ret = cmd_destroy_session(cmd_ctx->session,
3541 cmd_ctx->lsm->session.name);
3542 /*
3543 * Set session to NULL so we do not unlock it after
3544 * free.
3545 */
3546 cmd_ctx->session = NULL;
3547 break;
3548 }
3549 case LTTNG_LIST_DOMAINS:
3550 {
3551 ssize_t nb_dom;
3552 struct lttng_domain *domains;
3553
3554 nb_dom = cmd_list_domains(cmd_ctx->session, &domains);
3555 if (nb_dom < 0) {
3556 ret = -nb_dom;
3557 goto error;
3558 }
3559
3560 ret = setup_lttng_msg(cmd_ctx, nb_dom * sizeof(struct lttng_domain));
3561 if (ret < 0) {
3562 goto setup_error;
3563 }
3564
3565 /* Copy event list into message payload */
3566 memcpy(cmd_ctx->llm->payload, domains,
3567 nb_dom * sizeof(struct lttng_domain));
3568
3569 free(domains);
3570
3571 ret = LTTCOMM_OK;
3572 break;
3573 }
3574 case LTTNG_LIST_CHANNELS:
3575 {
3576 size_t nb_chan;
3577 struct lttng_channel *channels;
3578
3579 nb_chan = cmd_list_channels(cmd_ctx->lsm->domain.type,
3580 cmd_ctx->session, &channels);
3581 if (nb_chan < 0) {
3582 ret = -nb_chan;
3583 goto error;
3584 }
3585
3586 ret = setup_lttng_msg(cmd_ctx, nb_chan * sizeof(struct lttng_channel));
3587 if (ret < 0) {
3588 goto setup_error;
3589 }
3590
3591 /* Copy event list into message payload */
3592 memcpy(cmd_ctx->llm->payload, channels,
3593 nb_chan * sizeof(struct lttng_channel));
3594
3595 free(channels);
3596
3597 ret = LTTCOMM_OK;
3598 break;
3599 }
3600 case LTTNG_LIST_EVENTS:
3601 {
3602 ssize_t nb_event;
3603 struct lttng_event *events = NULL;
3604
3605 nb_event = cmd_list_events(cmd_ctx->lsm->domain.type, cmd_ctx->session,
3606 cmd_ctx->lsm->u.list.channel_name, &events);
3607 if (nb_event < 0) {
3608 ret = -nb_event;
3609 goto error;
3610 }
3611
3612 ret = setup_lttng_msg(cmd_ctx, nb_event * sizeof(struct lttng_event));
3613 if (ret < 0) {
3614 goto setup_error;
3615 }
3616
3617 /* Copy event list into message payload */
3618 memcpy(cmd_ctx->llm->payload, events,
3619 nb_event * sizeof(struct lttng_event));
3620
3621 free(events);
3622
3623 ret = LTTCOMM_OK;
3624 break;
3625 }
3626 case LTTNG_LIST_SESSIONS:
3627 {
3628 unsigned int nr_sessions;
3629
3630 session_lock_list();
3631 nr_sessions = lttng_sessions_count(
3632 LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds),
3633 LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds));
3634
3635 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_session) * nr_sessions);
3636 if (ret < 0) {
3637 session_unlock_list();
3638 goto setup_error;
3639 }
3640
3641 /* Filled the session array */
3642 list_lttng_sessions((struct lttng_session *)(cmd_ctx->llm->payload),
3643 LTTNG_SOCK_GET_UID_CRED(&cmd_ctx->creds),
3644 LTTNG_SOCK_GET_GID_CRED(&cmd_ctx->creds));
3645
3646 session_unlock_list();
3647
3648 ret = LTTCOMM_OK;
3649 break;
3650 }
3651 case LTTNG_CALIBRATE:
3652 {
3653 ret = cmd_calibrate(cmd_ctx->lsm->domain.type,
3654 &cmd_ctx->lsm->u.calibrate);
3655 break;
3656 }
3657 case LTTNG_REGISTER_CONSUMER:
3658 {
3659 ret = cmd_register_consumer(cmd_ctx->session, cmd_ctx->lsm->domain.type,
3660 cmd_ctx->lsm->u.reg.path);
3661 break;
3662 }
3663 default:
3664 ret = LTTCOMM_UND;
3665 break;
3666 }
3667
3668 error:
3669 if (cmd_ctx->llm == NULL) {
3670 DBG("Missing llm structure. Allocating one.");
3671 if (setup_lttng_msg(cmd_ctx, 0) < 0) {
3672 goto setup_error;
3673 }
3674 }
3675 /* Set return code */
3676 cmd_ctx->llm->ret_code = ret;
3677 setup_error:
3678 if (cmd_ctx->session) {
3679 session_unlock(cmd_ctx->session);
3680 }
3681 if (need_tracing_session) {
3682 session_unlock_list();
3683 }
3684 init_setup_error:
3685 return ret;
3686 }
3687
3688 /*
3689 * This thread manage all clients request using the unix client socket for
3690 * communication.
3691 */
3692 static void *thread_manage_clients(void *data)
3693 {
3694 int sock = -1, ret, i, pollfd;
3695 uint32_t revents, nb_fd;
3696 struct command_ctx *cmd_ctx = NULL;
3697 struct lttng_poll_event events;
3698
3699 DBG("[thread] Manage client started");
3700
3701 rcu_register_thread();
3702
3703 ret = lttcomm_listen_unix_sock(client_sock);
3704 if (ret < 0) {
3705 goto error;
3706 }
3707
3708 /*
3709 * Pass 2 as size here for the thread quit pipe and client_sock. Nothing
3710 * more will be added to this poll set.
3711 */
3712 ret = create_thread_poll_set(&events, 2);
3713 if (ret < 0) {
3714 goto error;
3715 }
3716
3717 /* Add the application registration socket */
3718 ret = lttng_poll_add(&events, client_sock, LPOLLIN | LPOLLPRI);
3719 if (ret < 0) {
3720 goto error;
3721 }
3722
3723 /*
3724 * Notify parent pid that we are ready to accept command for client side.
3725 */
3726 if (opt_sig_parent) {
3727 kill(ppid, SIGUSR1);
3728 }
3729
3730 while (1) {
3731 DBG("Accepting client command ...");
3732
3733 nb_fd = LTTNG_POLL_GETNB(&events);
3734
3735 /* Inifinite blocking call, waiting for transmission */
3736 restart:
3737 ret = lttng_poll_wait(&events, -1);
3738 if (ret < 0) {
3739 /*
3740 * Restart interrupted system call.
3741 */
3742 if (errno == EINTR) {
3743 goto restart;
3744 }
3745 goto error;
3746 }
3747
3748 for (i = 0; i < nb_fd; i++) {
3749 /* Fetch once the poll data */
3750 revents = LTTNG_POLL_GETEV(&events, i);
3751 pollfd = LTTNG_POLL_GETFD(&events, i);
3752
3753 /* Thread quit pipe has been closed. Killing thread. */
3754 ret = check_thread_quit_pipe(pollfd, revents);
3755 if (ret) {
3756 goto error;
3757 }
3758
3759 /* Event on the registration socket */
3760 if (pollfd == client_sock) {
3761 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
3762 ERR("Client socket poll error");
3763 goto error;
3764 }
3765 }
3766 }
3767
3768 DBG("Wait for client response");
3769
3770 sock = lttcomm_accept_unix_sock(client_sock);
3771 if (sock < 0) {
3772 goto error;
3773 }
3774
3775 /* Set socket option for credentials retrieval */
3776 ret = lttcomm_setsockopt_creds_unix_sock(sock);
3777 if (ret < 0) {
3778 goto error;
3779 }
3780
3781 /* Allocate context command to process the client request */
3782 cmd_ctx = zmalloc(sizeof(struct command_ctx));
3783 if (cmd_ctx == NULL) {
3784 PERROR("zmalloc cmd_ctx");
3785 goto error;
3786 }
3787
3788 /* Allocate data buffer for reception */
3789 cmd_ctx->lsm = zmalloc(sizeof(struct lttcomm_session_msg));
3790 if (cmd_ctx->lsm == NULL) {
3791 PERROR("zmalloc cmd_ctx->lsm");
3792 goto error;
3793 }
3794
3795 cmd_ctx->llm = NULL;
3796 cmd_ctx->session = NULL;
3797
3798 /*
3799 * Data is received from the lttng client. The struct
3800 * lttcomm_session_msg (lsm) contains the command and data request of
3801 * the client.
3802 */
3803 DBG("Receiving data from client ...");
3804 ret = lttcomm_recv_creds_unix_sock(sock, cmd_ctx->lsm,
3805 sizeof(struct lttcomm_session_msg), &cmd_ctx->creds);
3806 if (ret <= 0) {
3807 DBG("Nothing recv() from client... continuing");
3808 ret = close(sock);
3809 if (ret) {
3810 PERROR("close");
3811 }
3812 sock = -1;
3813 clean_command_ctx(&cmd_ctx);
3814 continue;
3815 }
3816
3817 // TODO: Validate cmd_ctx including sanity check for
3818 // security purpose.
3819
3820 rcu_thread_online();
3821 /*
3822 * This function dispatch the work to the kernel or userspace tracer
3823 * libs and fill the lttcomm_lttng_msg data structure of all the needed
3824 * informations for the client. The command context struct contains
3825 * everything this function may needs.
3826 */
3827 ret = process_client_msg(cmd_ctx);
3828 rcu_thread_offline();
3829 if (ret < 0) {
3830 /*
3831 * TODO: Inform client somehow of the fatal error. At
3832 * this point, ret < 0 means that a zmalloc failed
3833 * (ENOMEM). Error detected but still accept command.
3834 */
3835 clean_command_ctx(&cmd_ctx);
3836 continue;
3837 }
3838
3839 DBG("Sending response (size: %d, retcode: %s)",
3840 cmd_ctx->lttng_msg_size,
3841 lttng_strerror(-cmd_ctx->llm->ret_code));
3842 ret = send_unix_sock(sock, cmd_ctx->llm, cmd_ctx->lttng_msg_size);
3843 if (ret < 0) {
3844 ERR("Failed to send data back to client");
3845 }
3846
3847 /* End of transmission */
3848 ret = close(sock);
3849 if (ret) {
3850 PERROR("close");
3851 }
3852 sock = -1;
3853
3854 clean_command_ctx(&cmd_ctx);
3855 }
3856
3857 error:
3858 DBG("Client thread dying");
3859 unlink(client_unix_sock_path);
3860 if (client_sock >= 0) {
3861 ret = close(client_sock);
3862 if (ret) {
3863 PERROR("close");
3864 }
3865 }
3866 if (sock >= 0) {
3867 ret = close(sock);
3868 if (ret) {
3869 PERROR("close");
3870 }
3871 }
3872
3873 lttng_poll_clean(&events);
3874 clean_command_ctx(&cmd_ctx);
3875
3876 rcu_unregister_thread();
3877 return NULL;
3878 }
3879
3880
3881 /*
3882 * usage function on stderr
3883 */
3884 static void usage(void)
3885 {
3886 fprintf(stderr, "Usage: %s OPTIONS\n\nOptions:\n", progname);
3887 fprintf(stderr, " -h, --help Display this usage.\n");
3888 fprintf(stderr, " -c, --client-sock PATH Specify path for the client unix socket\n");
3889 fprintf(stderr, " -a, --apps-sock PATH Specify path for apps unix socket\n");
3890 fprintf(stderr, " --kconsumerd-err-sock PATH Specify path for the kernel consumer error socket\n");
3891 fprintf(stderr, " --kconsumerd-cmd-sock PATH Specify path for the kernel consumer command socket\n");
3892 fprintf(stderr, " --ustconsumerd32-err-sock PATH Specify path for the 32-bit UST consumer error socket\n");
3893 fprintf(stderr, " --ustconsumerd64-err-sock PATH Specify path for the 64-bit UST consumer error socket\n");
3894 fprintf(stderr, " --ustconsumerd32-cmd-sock PATH Specify path for the 32-bit UST consumer command socket\n");
3895 fprintf(stderr, " --ustconsumerd64-cmd-sock PATH Specify path for the 64-bit UST consumer command socket\n");
3896 fprintf(stderr, " --consumerd32-path PATH Specify path for the 32-bit UST consumer daemon binary\n");
3897 fprintf(stderr, " --consumerd32-libdir PATH Specify path for the 32-bit UST consumer daemon libraries\n");
3898 fprintf(stderr, " --consumerd64-path PATH Specify path for the 64-bit UST consumer daemon binary\n");
3899 fprintf(stderr, " --consumerd64-libdir PATH Specify path for the 64-bit UST consumer daemon libraries\n");
3900 fprintf(stderr, " -d, --daemonize Start as a daemon.\n");
3901 fprintf(stderr, " -g, --group NAME Specify the tracing group name. (default: tracing)\n");
3902 fprintf(stderr, " -V, --version Show version number.\n");
3903 fprintf(stderr, " -S, --sig-parent Send SIGCHLD to parent pid to notify readiness.\n");
3904 fprintf(stderr, " -q, --quiet No output at all.\n");
3905 fprintf(stderr, " -v, --verbose Verbose mode. Activate DBG() macro.\n");
3906 fprintf(stderr, " --verbose-consumer Verbose mode for consumer. Activate DBG() macro.\n");
3907 fprintf(stderr, " --no-kernel Disable kernel tracer\n");
3908 }
3909
3910 /*
3911 * daemon argument parsing
3912 */
3913 static int parse_args(int argc, char **argv)
3914 {
3915 int c;
3916
3917 static struct option long_options[] = {
3918 { "client-sock", 1, 0, 'c' },
3919 { "apps-sock", 1, 0, 'a' },
3920 { "kconsumerd-cmd-sock", 1, 0, 'C' },
3921 { "kconsumerd-err-sock", 1, 0, 'E' },
3922 { "ustconsumerd32-cmd-sock", 1, 0, 'G' },
3923 { "ustconsumerd32-err-sock", 1, 0, 'H' },
3924 { "ustconsumerd64-cmd-sock", 1, 0, 'D' },
3925 { "ustconsumerd64-err-sock", 1, 0, 'F' },
3926 { "consumerd32-path", 1, 0, 'u' },
3927 { "consumerd32-libdir", 1, 0, 'U' },
3928 { "consumerd64-path", 1, 0, 't' },
3929 { "consumerd64-libdir", 1, 0, 'T' },
3930 { "daemonize", 0, 0, 'd' },
3931 { "sig-parent", 0, 0, 'S' },
3932 { "help", 0, 0, 'h' },
3933 { "group", 1, 0, 'g' },
3934 { "version", 0, 0, 'V' },
3935 { "quiet", 0, 0, 'q' },
3936 { "verbose", 0, 0, 'v' },
3937 { "verbose-consumer", 0, 0, 'Z' },
3938 { "no-kernel", 0, 0, 'N' },
3939 { NULL, 0, 0, 0 }
3940 };
3941
3942 while (1) {
3943 int option_index = 0;
3944 c = getopt_long(argc, argv, "dhqvVSN" "a:c:g:s:C:E:D:F:Z:u:t",
3945 long_options, &option_index);
3946 if (c == -1) {
3947 break;
3948 }
3949
3950 switch (c) {
3951 case 0:
3952 fprintf(stderr, "option %s", long_options[option_index].name);
3953 if (optarg) {
3954 fprintf(stderr, " with arg %s\n", optarg);
3955 }
3956 break;
3957 case 'c':
3958 snprintf(client_unix_sock_path, PATH_MAX, "%s", optarg);
3959 break;
3960 case 'a':
3961 snprintf(apps_unix_sock_path, PATH_MAX, "%s", optarg);
3962 break;
3963 case 'd':
3964 opt_daemon = 1;
3965 break;
3966 case 'g':
3967 opt_tracing_group = optarg;
3968 break;
3969 case 'h':
3970 usage();
3971 exit(EXIT_FAILURE);
3972 case 'V':
3973 fprintf(stdout, "%s\n", VERSION);
3974 exit(EXIT_SUCCESS);
3975 case 'S':
3976 opt_sig_parent = 1;
3977 break;
3978 case 'E':
3979 snprintf(kconsumer_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3980 break;
3981 case 'C':
3982 snprintf(kconsumer_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3983 break;
3984 case 'F':
3985 snprintf(ustconsumer64_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3986 break;
3987 case 'D':
3988 snprintf(ustconsumer64_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3989 break;
3990 case 'H':
3991 snprintf(ustconsumer32_data.err_unix_sock_path, PATH_MAX, "%s", optarg);
3992 break;
3993 case 'G':
3994 snprintf(ustconsumer32_data.cmd_unix_sock_path, PATH_MAX, "%s", optarg);
3995 break;
3996 case 'N':
3997 opt_no_kernel = 1;
3998 break;
3999 case 'q':
4000 lttng_opt_quiet = 1;
4001 break;
4002 case 'v':
4003 /* Verbose level can increase using multiple -v */
4004 lttng_opt_verbose += 1;
4005 break;
4006 case 'Z':
4007 opt_verbose_consumer += 1;
4008 break;
4009 case 'u':
4010 consumerd32_bin= optarg;
4011 break;
4012 case 'U':
4013 consumerd32_libdir = optarg;
4014 break;
4015 case 't':
4016 consumerd64_bin = optarg;
4017 break;
4018 case 'T':
4019 consumerd64_libdir = optarg;
4020 break;
4021 default:
4022 /* Unknown option or other error.
4023 * Error is printed by getopt, just return */
4024 return -1;
4025 }
4026 }
4027
4028 return 0;
4029 }
4030
4031 /*
4032 * Creates the two needed socket by the daemon.
4033 * apps_sock - The communication socket for all UST apps.
4034 * client_sock - The communication of the cli tool (lttng).
4035 */
4036 static int init_daemon_socket(void)
4037 {
4038 int ret = 0;
4039 mode_t old_umask;
4040
4041 old_umask = umask(0);
4042
4043 /* Create client tool unix socket */
4044 client_sock = lttcomm_create_unix_sock(client_unix_sock_path);
4045 if (client_sock < 0) {
4046 ERR("Create unix sock failed: %s", client_unix_sock_path);
4047 ret = -1;
4048 goto end;
4049 }
4050
4051 /* File permission MUST be 660 */
4052 ret = chmod(client_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
4053 if (ret < 0) {
4054 ERR("Set file permissions failed: %s", client_unix_sock_path);
4055 PERROR("chmod");
4056 goto end;
4057 }
4058
4059 /* Create the application unix socket */
4060 apps_sock = lttcomm_create_unix_sock(apps_unix_sock_path);
4061 if (apps_sock < 0) {
4062 ERR("Create unix sock failed: %s", apps_unix_sock_path);
4063 ret = -1;
4064 goto end;
4065 }
4066
4067 /* File permission MUST be 666 */
4068 ret = chmod(apps_unix_sock_path,
4069 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
4070 if (ret < 0) {
4071 ERR("Set file permissions failed: %s", apps_unix_sock_path);
4072 PERROR("chmod");
4073 goto end;
4074 }
4075
4076 end:
4077 umask(old_umask);
4078 return ret;
4079 }
4080
4081 /*
4082 * Check if the global socket is available, and if a daemon is answering at the
4083 * other side. If yes, error is returned.
4084 */
4085 static int check_existing_daemon(void)
4086 {
4087 /* Is there anybody out there ? */
4088 if (lttng_session_daemon_alive()) {
4089 return -EEXIST;
4090 }
4091
4092 return 0;
4093 }
4094
4095 /*
4096 * Set the tracing group gid onto the client socket.
4097 *
4098 * Race window between mkdir and chown is OK because we are going from more
4099 * permissive (root.root) to less permissive (root.tracing).
4100 */
4101 static int set_permissions(char *rundir)
4102 {
4103 int ret;
4104 gid_t gid;
4105
4106 gid = allowed_group();
4107 if (gid < 0) {
4108 WARN("No tracing group detected");
4109 ret = 0;
4110 goto end;
4111 }
4112
4113 /* Set lttng run dir */
4114 ret = chown(rundir, 0, gid);
4115 if (ret < 0) {
4116 ERR("Unable to set group on %s", rundir);
4117 PERROR("chown");
4118 }
4119
4120 /* Ensure tracing group can search the run dir */
4121 ret = chmod(rundir, S_IRWXU | S_IXGRP | S_IXOTH);
4122 if (ret < 0) {
4123 ERR("Unable to set permissions on %s", rundir);
4124 PERROR("chmod");
4125 }
4126
4127 /* lttng client socket path */
4128 ret = chown(client_unix_sock_path, 0, gid);
4129 if (ret < 0) {
4130 ERR("Unable to set group on %s", client_unix_sock_path);
4131 PERROR("chown");
4132 }
4133
4134 /* kconsumer error socket path */
4135 ret = chown(kconsumer_data.err_unix_sock_path, 0, gid);
4136 if (ret < 0) {
4137 ERR("Unable to set group on %s", kconsumer_data.err_unix_sock_path);
4138 PERROR("chown");
4139 }
4140
4141 /* 64-bit ustconsumer error socket path */
4142 ret = chown(ustconsumer64_data.err_unix_sock_path, 0, gid);
4143 if (ret < 0) {
4144 ERR("Unable to set group on %s", ustconsumer64_data.err_unix_sock_path);
4145 PERROR("chown");
4146 }
4147
4148 /* 32-bit ustconsumer compat32 error socket path */
4149 ret = chown(ustconsumer32_data.err_unix_sock_path, 0, gid);
4150 if (ret < 0) {
4151 ERR("Unable to set group on %s", ustconsumer32_data.err_unix_sock_path);
4152 PERROR("chown");
4153 }
4154
4155 DBG("All permissions are set");
4156
4157 end:
4158 return ret;
4159 }
4160
4161 /*
4162 * Create the pipe used to wake up the kernel thread.
4163 * Closed in cleanup().
4164 */
4165 static int create_kernel_poll_pipe(void)
4166 {
4167 int ret, i;
4168
4169 ret = pipe(kernel_poll_pipe);
4170 if (ret < 0) {
4171 PERROR("kernel poll pipe");
4172 goto error;
4173 }
4174
4175 for (i = 0; i < 2; i++) {
4176 ret = fcntl(kernel_poll_pipe[i], F_SETFD, FD_CLOEXEC);
4177 if (ret < 0) {
4178 PERROR("fcntl kernel_poll_pipe");
4179 goto error;
4180 }
4181 }
4182
4183 error:
4184 return ret;
4185 }
4186
4187 /*
4188 * Create the application command pipe to wake thread_manage_apps.
4189 * Closed in cleanup().
4190 */
4191 static int create_apps_cmd_pipe(void)
4192 {
4193 int ret, i;
4194
4195 ret = pipe(apps_cmd_pipe);
4196 if (ret < 0) {
4197 PERROR("apps cmd pipe");
4198 goto error;
4199 }
4200
4201 for (i = 0; i < 2; i++) {
4202 ret = fcntl(apps_cmd_pipe[i], F_SETFD, FD_CLOEXEC);
4203 if (ret < 0) {
4204 PERROR("fcntl apps_cmd_pipe");
4205 goto error;
4206 }
4207 }
4208
4209 error:
4210 return ret;
4211 }
4212
4213 /*
4214 * Create the lttng run directory needed for all global sockets and pipe.
4215 */
4216 static int create_lttng_rundir(const char *rundir)
4217 {
4218 int ret;
4219
4220 DBG3("Creating LTTng run directory: %s", rundir);
4221
4222 ret = mkdir(rundir, S_IRWXU);
4223 if (ret < 0) {
4224 if (errno != EEXIST) {
4225 ERR("Unable to create %s", rundir);
4226 goto error;
4227 } else {
4228 ret = 0;
4229 }
4230 }
4231
4232 error:
4233 return ret;
4234 }
4235
4236 /*
4237 * Setup sockets and directory needed by the kconsumerd communication with the
4238 * session daemon.
4239 */
4240 static int set_consumer_sockets(struct consumer_data *consumer_data,
4241 const char *rundir)
4242 {
4243 int ret;
4244 char path[PATH_MAX];
4245
4246 switch (consumer_data->type) {
4247 case LTTNG_CONSUMER_KERNEL:
4248 snprintf(path, PATH_MAX, DEFAULT_KCONSUMERD_PATH, rundir);
4249 break;
4250 case LTTNG_CONSUMER64_UST:
4251 snprintf(path, PATH_MAX, DEFAULT_USTCONSUMERD64_PATH, rundir);
4252 break;
4253 case LTTNG_CONSUMER32_UST:
4254 snprintf(path, PATH_MAX, DEFAULT_USTCONSUMERD32_PATH, rundir);
4255 break;
4256 default:
4257 ERR("Consumer type unknown");
4258 ret = -EINVAL;
4259 goto error;
4260 }
4261
4262 DBG2("Creating consumer directory: %s", path);
4263
4264 ret = mkdir(path, S_IRWXU);
4265 if (ret < 0) {
4266 if (errno != EEXIST) {
4267 PERROR("mkdir");
4268 ERR("Failed to create %s", path);
4269 goto error;
4270 }
4271 ret = -1;
4272 }
4273
4274 /* Create the kconsumerd error unix socket */
4275 consumer_data->err_sock =
4276 lttcomm_create_unix_sock(consumer_data->err_unix_sock_path);
4277 if (consumer_data->err_sock < 0) {
4278 ERR("Create unix sock failed: %s", consumer_data->err_unix_sock_path);
4279 ret = -1;
4280 goto error;
4281 }
4282
4283 /* File permission MUST be 660 */
4284 ret = chmod(consumer_data->err_unix_sock_path,
4285 S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
4286 if (ret < 0) {
4287 ERR("Set file permissions failed: %s", consumer_data->err_unix_sock_path);
4288 PERROR("chmod");
4289 goto error;
4290 }
4291
4292 error:
4293 return ret;
4294 }
4295
4296 /*
4297 * Signal handler for the daemon
4298 *
4299 * Simply stop all worker threads, leaving main() return gracefully after
4300 * joining all threads and calling cleanup().
4301 */
4302 static void sighandler(int sig)
4303 {
4304 switch (sig) {
4305 case SIGPIPE:
4306 DBG("SIGPIPE caught");
4307 return;
4308 case SIGINT:
4309 DBG("SIGINT caught");
4310 stop_threads();
4311 break;
4312 case SIGTERM:
4313 DBG("SIGTERM caught");
4314 stop_threads();
4315 break;
4316 default:
4317 break;
4318 }
4319 }
4320
4321 /*
4322 * Setup signal handler for :
4323 * SIGINT, SIGTERM, SIGPIPE
4324 */
4325 static int set_signal_handler(void)
4326 {
4327 int ret = 0;
4328 struct sigaction sa;
4329 sigset_t sigset;
4330
4331 if ((ret = sigemptyset(&sigset)) < 0) {
4332 PERROR("sigemptyset");
4333 return ret;
4334 }
4335
4336 sa.sa_handler = sighandler;
4337 sa.sa_mask = sigset;
4338 sa.sa_flags = 0;
4339 if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
4340 PERROR("sigaction");
4341 return ret;
4342 }
4343
4344 if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) {
4345 PERROR("sigaction");
4346 return ret;
4347 }
4348
4349 if ((ret = sigaction(SIGPIPE, &sa, NULL)) < 0) {
4350 PERROR("sigaction");
4351 return ret;
4352 }
4353
4354 DBG("Signal handler set for SIGTERM, SIGPIPE and SIGINT");
4355
4356 return ret;
4357 }
4358
4359 /*
4360 * Set open files limit to unlimited. This daemon can open a large number of
4361 * file descriptors in order to consumer multiple kernel traces.
4362 */
4363 static void set_ulimit(void)
4364 {
4365 int ret;
4366 struct rlimit lim;
4367
4368 /* The kernel does not allowed an infinite limit for open files */
4369 lim.rlim_cur = 65535;
4370 lim.rlim_max = 65535;
4371
4372 ret = setrlimit(RLIMIT_NOFILE, &lim);
4373 if (ret < 0) {
4374 PERROR("failed to set open files limit");
4375 }
4376 }
4377
4378 /*
4379 * main
4380 */
4381 int main(int argc, char **argv)
4382 {
4383 int ret = 0;
4384 void *status;
4385 const char *home_path;
4386
4387 init_kernel_workarounds();
4388
4389 rcu_register_thread();
4390
4391 /* Create thread quit pipe */
4392 if ((ret = init_thread_quit_pipe()) < 0) {
4393 goto error;
4394 }
4395
4396 setup_consumerd_path();
4397
4398 /* Parse arguments */
4399 progname = argv[0];
4400 if ((ret = parse_args(argc, argv) < 0)) {
4401 goto error;
4402 }
4403
4404 /* Daemonize */
4405 if (opt_daemon) {
4406 ret = daemon(0, 0);
4407 if (ret < 0) {
4408 PERROR("daemon");
4409 goto error;
4410 }
4411 }
4412
4413 /* Check if daemon is UID = 0 */
4414 is_root = !getuid();
4415
4416 if (is_root) {
4417 rundir = strdup(DEFAULT_LTTNG_RUNDIR);
4418
4419 /* Create global run dir with root access */
4420 ret = create_lttng_rundir(rundir);
4421 if (ret < 0) {
4422 goto error;
4423 }
4424
4425 if (strlen(apps_unix_sock_path) == 0) {
4426 snprintf(apps_unix_sock_path, PATH_MAX,
4427 DEFAULT_GLOBAL_APPS_UNIX_SOCK);
4428 }
4429
4430 if (strlen(client_unix_sock_path) == 0) {
4431 snprintf(client_unix_sock_path, PATH_MAX,
4432 DEFAULT_GLOBAL_CLIENT_UNIX_SOCK);
4433 }
4434
4435 /* Set global SHM for ust */
4436 if (strlen(wait_shm_path) == 0) {
4437 snprintf(wait_shm_path, PATH_MAX,
4438 DEFAULT_GLOBAL_APPS_WAIT_SHM_PATH);
4439 }
4440
4441 /* Setup kernel consumerd path */
4442 snprintf(kconsumer_data.err_unix_sock_path, PATH_MAX,
4443 DEFAULT_KCONSUMERD_ERR_SOCK_PATH, rundir);
4444 snprintf(kconsumer_data.cmd_unix_sock_path, PATH_MAX,
4445 DEFAULT_KCONSUMERD_CMD_SOCK_PATH, rundir);
4446
4447 DBG2("Kernel consumer err path: %s",
4448 kconsumer_data.err_unix_sock_path);
4449 DBG2("Kernel consumer cmd path: %s",
4450 kconsumer_data.cmd_unix_sock_path);
4451 } else {
4452 home_path = get_home_dir();
4453 if (home_path == NULL) {
4454 /* TODO: Add --socket PATH option */
4455 ERR("Can't get HOME directory for sockets creation.");
4456 ret = -EPERM;
4457 goto error;
4458 }
4459
4460 /*
4461 * Create rundir from home path. This will create something like
4462 * $HOME/.lttng
4463 */
4464 ret = asprintf(&rundir, DEFAULT_LTTNG_HOME_RUNDIR, home_path);
4465 if (ret < 0) {
4466 ret = -ENOMEM;
4467 goto error;
4468 }
4469
4470 ret = create_lttng_rundir(rundir);
4471 if (ret < 0) {
4472 goto error;
4473 }
4474
4475 if (strlen(apps_unix_sock_path) == 0) {
4476 snprintf(apps_unix_sock_path, PATH_MAX,
4477 DEFAULT_HOME_APPS_UNIX_SOCK, home_path);
4478 }
4479
4480 /* Set the cli tool unix socket path */
4481 if (strlen(client_unix_sock_path) == 0) {
4482 snprintf(client_unix_sock_path, PATH_MAX,
4483 DEFAULT_HOME_CLIENT_UNIX_SOCK, home_path);
4484 }
4485
4486 /* Set global SHM for ust */
4487 if (strlen(wait_shm_path) == 0) {
4488 snprintf(wait_shm_path, PATH_MAX,
4489 DEFAULT_HOME_APPS_WAIT_SHM_PATH, geteuid());
4490 }
4491 }
4492
4493 DBG("Client socket path %s", client_unix_sock_path);
4494 DBG("Application socket path %s", apps_unix_sock_path);
4495 DBG("LTTng run directory path: %s", rundir);
4496
4497 /* 32 bits consumerd path setup */
4498 snprintf(ustconsumer32_data.err_unix_sock_path, PATH_MAX,
4499 DEFAULT_USTCONSUMERD32_ERR_SOCK_PATH, rundir);
4500 snprintf(ustconsumer32_data.cmd_unix_sock_path, PATH_MAX,
4501 DEFAULT_USTCONSUMERD32_CMD_SOCK_PATH, rundir);
4502
4503 DBG2("UST consumer 32 bits err path: %s",
4504 ustconsumer32_data.err_unix_sock_path);
4505 DBG2("UST consumer 32 bits cmd path: %s",
4506 ustconsumer32_data.cmd_unix_sock_path);
4507
4508 /* 64 bits consumerd path setup */
4509 snprintf(ustconsumer64_data.err_unix_sock_path, PATH_MAX,
4510 DEFAULT_USTCONSUMERD64_ERR_SOCK_PATH, rundir);
4511 snprintf(ustconsumer64_data.cmd_unix_sock_path, PATH_MAX,
4512 DEFAULT_USTCONSUMERD64_CMD_SOCK_PATH, rundir);
4513
4514 DBG2("UST consumer 64 bits err path: %s",
4515 ustconsumer64_data.err_unix_sock_path);
4516 DBG2("UST consumer 64 bits cmd path: %s",
4517 ustconsumer64_data.cmd_unix_sock_path);
4518
4519 /*
4520 * See if daemon already exist.
4521 */
4522 if ((ret = check_existing_daemon()) < 0) {
4523 ERR("Already running daemon.\n");
4524 /*
4525 * We do not goto exit because we must not cleanup()
4526 * because a daemon is already running.
4527 */
4528 goto error;
4529 }
4530
4531 /*
4532 * Init UST app hash table. Alloc hash table before this point since
4533 * cleanup() can get called after that point.
4534 */
4535 ust_app_ht_alloc();
4536
4537 /* After this point, we can safely call cleanup() with "goto exit" */
4538
4539 /*
4540 * These actions must be executed as root. We do that *after* setting up
4541 * the sockets path because we MUST make the check for another daemon using
4542 * those paths *before* trying to set the kernel consumer sockets and init
4543 * kernel tracer.
4544 */
4545 if (is_root) {
4546 ret = set_consumer_sockets(&kconsumer_data, rundir);
4547 if (ret < 0) {
4548 goto exit;
4549 }
4550
4551 /* Setup kernel tracer */
4552 if (!opt_no_kernel) {
4553 init_kernel_tracer();
4554 }
4555
4556 /* Set ulimit for open files */
4557 set_ulimit();
4558 }
4559
4560 ret = set_consumer_sockets(&ustconsumer64_data, rundir);
4561 if (ret < 0) {
4562 goto exit;
4563 }
4564
4565 ret = set_consumer_sockets(&ustconsumer32_data, rundir);
4566 if (ret < 0) {
4567 goto exit;
4568 }
4569
4570 if ((ret = set_signal_handler()) < 0) {
4571 goto exit;
4572 }
4573
4574 /* Setup the needed unix socket */
4575 if ((ret = init_daemon_socket()) < 0) {
4576 goto exit;
4577 }
4578
4579 /* Set credentials to socket */
4580 if (is_root && ((ret = set_permissions(rundir)) < 0)) {
4581 goto exit;
4582 }
4583
4584 /* Get parent pid if -S, --sig-parent is specified. */
4585 if (opt_sig_parent) {
4586 ppid = getppid();
4587 }
4588
4589 /* Setup the kernel pipe for waking up the kernel thread */
4590 if ((ret = create_kernel_poll_pipe()) < 0) {
4591 goto exit;
4592 }
4593
4594 /* Setup the thread apps communication pipe. */
4595 if ((ret = create_apps_cmd_pipe()) < 0) {
4596 goto exit;
4597 }
4598
4599 /* Init UST command queue. */
4600 cds_wfq_init(&ust_cmd_queue.queue);
4601
4602 /*
4603 * Get session list pointer. This pointer MUST NOT be free(). This list is
4604 * statically declared in session.c
4605 */
4606 session_list_ptr = session_get_list();
4607
4608 /* Set up max poll set size */
4609 lttng_poll_set_max_size();
4610
4611 /* Create thread to manage the client socket */
4612 ret = pthread_create(&client_thread, NULL,
4613 thread_manage_clients, (void *) NULL);
4614 if (ret != 0) {
4615 PERROR("pthread_create clients");
4616 goto exit_client;
4617 }
4618
4619 /* Create thread to dispatch registration */
4620 ret = pthread_create(&dispatch_thread, NULL,
4621 thread_dispatch_ust_registration, (void *) NULL);
4622 if (ret != 0) {
4623 PERROR("pthread_create dispatch");
4624 goto exit_dispatch;
4625 }
4626
4627 /* Create thread to manage application registration. */
4628 ret = pthread_create(&reg_apps_thread, NULL,
4629 thread_registration_apps, (void *) NULL);
4630 if (ret != 0) {
4631 PERROR("pthread_create registration");
4632 goto exit_reg_apps;
4633 }
4634
4635 /* Create thread to manage application socket */
4636 ret = pthread_create(&apps_thread, NULL,
4637 thread_manage_apps, (void *) NULL);
4638 if (ret != 0) {
4639 PERROR("pthread_create apps");
4640 goto exit_apps;
4641 }
4642
4643 /* Create kernel thread to manage kernel event */
4644 ret = pthread_create(&kernel_thread, NULL,
4645 thread_manage_kernel, (void *) NULL);
4646 if (ret != 0) {
4647 PERROR("pthread_create kernel");
4648 goto exit_kernel;
4649 }
4650
4651 ret = pthread_join(kernel_thread, &status);
4652 if (ret != 0) {
4653 PERROR("pthread_join");
4654 goto error; /* join error, exit without cleanup */
4655 }
4656
4657 exit_kernel:
4658 ret = pthread_join(apps_thread, &status);
4659 if (ret != 0) {
4660 PERROR("pthread_join");
4661 goto error; /* join error, exit without cleanup */
4662 }
4663
4664 exit_apps:
4665 ret = pthread_join(reg_apps_thread, &status);
4666 if (ret != 0) {
4667 PERROR("pthread_join");
4668 goto error; /* join error, exit without cleanup */
4669 }
4670
4671 exit_reg_apps:
4672 ret = pthread_join(dispatch_thread, &status);
4673 if (ret != 0) {
4674 PERROR("pthread_join");
4675 goto error; /* join error, exit without cleanup */
4676 }
4677
4678 exit_dispatch:
4679 ret = pthread_join(client_thread, &status);
4680 if (ret != 0) {
4681 PERROR("pthread_join");
4682 goto error; /* join error, exit without cleanup */
4683 }
4684
4685 ret = join_consumer_thread(&kconsumer_data);
4686 if (ret != 0) {
4687 PERROR("join_consumer");
4688 goto error; /* join error, exit without cleanup */
4689 }
4690
4691 exit_client:
4692 exit:
4693 /*
4694 * cleanup() is called when no other thread is running.
4695 */
4696 rcu_thread_online();
4697 cleanup();
4698 rcu_thread_offline();
4699 rcu_unregister_thread();
4700 if (!ret) {
4701 exit(EXIT_SUCCESS);
4702 }
4703 error:
4704 exit(EXIT_FAILURE);
4705 }
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